Complete Biology Exam Study Guide - 120 Questions Answered

1. Biology: its tasks, object and research methods

Biology is the science that studies life and living organisms. Its main tasks include:

• Understanding the structure and function of living systems
• Investigating the mechanisms of life processes
• Studying the diversity of life forms
• Exploring the relationships between organisms and their environment

Objects of study: All living organisms from viruses to complex multicellular organisms, their structures, functions, and interactions.

Research methods: Observation, experimentation, modeling, comparative analysis, microscopy, biochemical analysis, genetic analysis, and molecular techniques.

2. The essence of life, the levels of organization of the living. The fundamental properties of the living, the cell as an elementary biological unit

Essence of life: Life is characterized by complex organization, metabolism, homeostasis, growth, reproduction, response to stimuli, and evolution.

Levels of organization:

• Molecular level (DNA, proteins, lipids)
• Cellular level (prokaryotic and eukaryotic cells)
• Tissue level (groups of similar cells)
• Organ level (tissues working together)
• Organ system level (organs functioning together)
• Organism level (complete individual)
• Population level (same species in area)
• Community level (different species interacting)
• Ecosystem level (living and non-living components)
• Biosphere level (global ecosystem)

Fundamental properties: Metabolism, homeostasis, growth, reproduction, heredity, variability, irritability, and adaptation.

Cell as elementary unit: The cell is the smallest unit that exhibits all properties of life and can exist independently.

3. Cell theory: the main stages of development

Main stages:

1. Antonie van Leeuwenhoek (1670s): First observed microorganisms using microscopes
2. Robert Hooke (1665): Coined the term "cell" observing cork tissue
3. Matthias Schleiden (1838): Proposed that all plants are made of cells
4. Theodor Schwann (1839): Extended cell theory to animals
5. Rudolf Virchow (1855): Added "omnis cellula e cellula" (all cells come from cells)

Modern cell theory principles:

• All living things are made of one or more cells
• The cell is the basic unit of life
• All cells arise from pre-existing cells

4. Types of cell organization. Pro- and eukaryotic cells, structural features and vital functions

Prokaryotic cells:

• No membrane-bound nucleus
• Genetic material freely distributed in cytoplasm
• No membrane-bound organelles
• Ribosomes are 70S
• Cell wall usually present
• Examples: bacteria, archaea

Eukaryotic cells:

• Membrane-bound nucleus
• Genetic material enclosed in nucleus
• Membrane-bound organelles present
• Ribosomes are 80S (cytoplasmic)
• May or may not have cell wall
• Examples: plants, animals, fungi, protists

Vital functions: Both types perform metabolism, growth, reproduction, response to stimuli, and maintain homeostasis.

5. Viruses: structure, organization of genetic material, medical significance

Structure:

• Nucleic acid core (DNA or RNA)
• Protein coat (capsid)
• Some have envelope from host cell membrane
• No cellular structure

Genetic material organization:

• Can be DNA or RNA
• Single or double-stranded
• Linear or circular
• Contains genes for replication and capsid proteins

Medical significance:

• Cause many diseases (COVID-19, influenza, HIV, hepatitis)
• Used in gene therapy
• Vaccine development
• Oncogenic viruses cause cancer

6. Cell as an open system: Flows of matter, energy and information in the cell

Matter flow:

• Nutrients enter cell
• Waste products exit cell
• Continuous exchange with environment

Energy flow:

• Energy input through food/sunlight
• Energy conversion (ATP synthesis)
• Energy utilization for cellular processes
• Heat production and loss

Information flow:

• DNA → RNA → Protein (central dogma)
• Signal transduction pathways
• Cellular communication
• Regulatory mechanisms

7. Elementary chemical composition of the living. Water and low molecular weight cell compounds

Elementary composition:

• Carbon (C): 18% - forms organic compounds
• Oxygen (O): 65% - essential for respiration
• Hydrogen (H): 10% - component of water and organic molecules
• Nitrogen (N): 3% - essential for proteins and nucleic acids
• Phosphorus (P): 1% - nucleic acids, ATP, membranes
• Sulfur (S): 0.25% - proteins (cysteine, methionine)

Water (H₂O):

• 60-70% of cell mass
• Universal solvent
• Participates in metabolic reactions
• Maintains cell shape and volume
• Temperature regulation

Low molecular weight compounds:

• Amino acids, sugars, nucleotides
• Vitamins, hormones, neurotransmitters
• Ions (Na⁺, K⁺, Ca²⁺, Cl⁻)
• Gases (O₂, CO₂)

8. The structure and biological functions of cell proteins

Structure:

• Primary: amino acid sequence
• Secondary: α-helices and β-sheets
• Tertiary: 3D folding
• Quaternary: multiple polypeptide chains

Functions:

• Enzymatic: catalyze biochemical reactions
• Structural: provide cell shape and support
• Transport: move substances across membranes
• Storage: store amino acids and metal ions
• Hormonal: regulate physiological processes
• Receptor: detect and respond to signals
• Contractile: enable movement
• Defensive: protect against pathogens

9. The structure and biological functions of cell lipids

Structure:

• Fatty acids: long hydrocarbon chains
• Glycerol backbone (in most lipids)
• Phosphate groups (in phospholipids)
• Steroid ring structure (in steroids)

Types and functions:

• Phospholipids: membrane structure, signaling
• Triglycerides: energy storage, insulation
• Steroids: hormones (testosterone, estrogen), membrane fluidity
• Waxes: protective coatings

10. The structure and biological functions of carbohydrate cells

Structure:

• Monosaccharides: simple sugars (glucose, fructose)
• Disaccharides: two monosaccharides (sucrose, lactose)
• Polysaccharides: many monosaccharides (starch, glycogen, cellulose)

Functions:

• Energy source: glucose metabolism
• Energy storage: glycogen (animals), starch (plants)
• Structural: cellulose (plant cell walls), chitin (fungal cell walls)
• Cell recognition: glycoproteins and glycolipids
• Signaling: various carbohydrate-based signals

11. The structure and biological functions of nucleic acids

Structure:

• Nucleotides: phosphate + pentose sugar + nitrogenous base
• DNA: double helix, deoxyribose, A-T and G-C base pairs
• RNA: single strand, ribose, A-U and G-C base pairs

Functions:

• DNA: genetic information storage, replication, transcription
• mRNA: carries genetic information from DNA to ribosomes
• tRNA: transfers amino acids during protein synthesis
• rRNA: structural component of ribosomes
• Regulatory RNAs: control gene expression

12. The structure and biological functions of the plasma membrane

Structure:

• Phospholipid bilayer
• Integral and peripheral proteins
• Cholesterol (in animal cells)
• Carbohydrate chains (glycocalyx)
• Fluid mosaic model

Functions:

• Selective permeability
• Cell recognition and communication
• Signal transduction
• Transport of materials
• Maintaining cell shape
• Enzyme activity sites

13. Transport through the plasma membrane: active and passive, their types, exocytosis, endocytosis

Passive transport (no energy required):

• Simple diffusion: small molecules through lipid bilayer
• Facilitated diffusion: through channel or carrier proteins
• Osmosis: water movement across membrane

Active transport (energy required):

• Primary active transport: uses ATP directly
• Secondary active transport: uses ion gradients
• Examples: Na⁺/K⁺ pump, glucose transporters

Exocytosis: vesicles fuse with membrane to release contents outside Endocytosis: membrane invaginates to bring materials inside

• Phagocytosis: engulfing large particles
• Pinocytosis: engulfing liquids
• Receptor-mediated endocytosis: specific molecule uptake

14. Contacts and intercellular communications of a eukaryotic cell

Types of cell contacts:

• Tight junctions: seal between cells, prevent leakage
• Gap junctions: allow direct communication between cells
• Desmosomes: provide mechanical strength
• Adherens junctions: cell-cell adhesion

Communication mechanisms:

• Direct contact through gap junctions
• Chemical signals (hormones, neurotransmitters)
• Electrical signals
• Mechanical signals

15. The cell as an integral structure. The colloidal system of the cytoplasm (hyaloplasm)

Cytoplasm as colloidal system:

• Gel-sol transitions
• Contains dissolved substances and suspended particles
• Provides medium for cellular reactions
• Maintains cell shape and organelle positioning

Hyaloplasm (cytosol):

• Aqueous solution of ions, small molecules, and proteins
• Site of many metabolic reactions
• Maintains osmotic balance
• Provides structural support through cytoskeleton

16. Ultrastructural organization of human cells

Key ultrastructural features:

• Plasma membrane with microvilli
• Nucleus with nuclear envelope and nucleolus
• Extensive endoplasmic reticulum
• Well-developed Golgi apparatus
• Numerous mitochondria
• Various types of vesicles and vacuoles
• Cytoskeletal elements
• Centrioles and centrosome

17. Structural organization of a eukaryotic cell: 1-membrane, 2-membrane and non-membrane cell organelles. Inclusions

Single-membrane organelles:

• Endoplasmic reticulum (rough and smooth)
• Golgi apparatus
• Lysosomes
• Peroxisomes
• Vacuoles

Double-membrane organelles:

• Nucleus
• Mitochondria
• Chloroplasts (in plants)

Non-membrane organelles:

• Ribosomes
• Centrosomes
• Cytoskeleton (microfilaments, microtubules, intermediate filaments)

Inclusions:

• Glycogen granules
• Lipid droplets
• Pigment granules
• Crystals

18. Single-membrane cell organelles: tubular and vacuolar cell systems – EPS, Golgi Complex, dictiosomes, lysosomes, microorganisms, peroxisomes. Their structure and functions

Endoplasmic Reticulum (ER):

• Rough ER: ribosomes attached, protein synthesis and modification
• Smooth ER: lipid synthesis, detoxification, calcium storage

Golgi Complex:

• Stacks of flattened cisternae
• Modifies, packages, and ships proteins
• Forms lysosomes and secretory vesicles

Lysosomes:

• Contain digestive enzymes
• Intracellular digestion
• Autophagy and apoptosis

Peroxisomes:

• Contain catalase and other oxidative enzymes
• Detoxification
• Fatty acid oxidation

19. Tubular cell structures: centrioles, basal organisms, flagella, cilia, cytoskeletal elements

Centrioles:

• Pair of cylindrical structures
• Organize microtubules
• Important in cell division

Basal bodies:

• Anchor cilia and flagella
• Similar structure to centrioles

Flagella and Cilia:

• Motile appendages
• 9+2 microtubule arrangement
• Movement by dynein motor proteins

Cytoskeletal elements:

• Microfilaments (actin): cell shape, muscle contraction
• Microtubules (tubulin): intracellular transport, cell division
• Intermediate filaments: structural support

20. The structure and functions of mitochondria

Structure:

• Double membrane (outer and inner)
• Cristae: folds of inner membrane
• Matrix: inner compartment
• Own DNA and ribosomes

Functions:

• ATP synthesis (oxidative phosphorylation)
• Cellular respiration
• Fatty acid oxidation
• Calcium storage
• Apoptosis regulation
• Heat production

21. Inclusions of cell

Types of inclusions:

• Glycogen granules: glucose storage
• Lipid droplets: fat storage
• Pigment granules: melanin, lipofuscin
• Protein inclusions: various storage proteins
• Crystalline inclusions: calcium phosphate, uric acid

Functions:

• Energy storage
• Structural materials
• Waste products
• Metabolic intermediates

22. The structure and functions of the cell nucleus. The structure and organization of chromatin: euchromatin and heterochromatin, its role in the regulation of gene activity

Nuclear structure:

• Nuclear envelope: double membrane with pores
• Nucleolus: ribosome assembly
• Nucleoplasm: nuclear matrix
• Chromatin: DNA-protein complex

Chromatin types:

• Euchromatin: loosely packed, transcriptionally active
• Heterochromatin: tightly packed, transcriptionally inactive
  • Constitutive: permanently inactive
  • Facultative: conditionally inactive

Gene regulation role:

• Chromatin structure controls gene accessibility
• Histone modifications affect transcription
• DNA methylation silences genes

23. Levels of chromatin organization: nucleosome filament, elementary chromatin fibril, interphase chromoneme, metaphase chromatid, their significance in the mitotic cycle

Levels of organization:

1. Nucleosome filament: DNA wrapped around histone octamers
2. Elementary chromatin fibril: 30nm fiber, compacted nucleosomes
3. Interphase chromoneme: further condensed during interphase
4. Metaphase chromatid: maximally condensed for chromosome separation

Significance in mitotic cycle:

• Progressive condensation prepares chromosomes for division
• Ensures accurate chromosome segregation
• Prevents DNA damage during cell division

24. Polytene chromosomes, chromosomes such as lamp brushes, their structure and functional significance

Polytene chromosomes:

• Found in Drosophila salivary glands
• Multiple DNA replications without separation
• Bands represent active gene regions
• Used for genetic mapping

Lampbrush chromosomes:

• Found in oocytes during meiosis
• Loops of DNA extending from chromosome axis
• Sites of active RNA transcription
• Important for oocyte development

25. Metabolism and energy charge: the role of ATP in the life of cells

Metabolism:

• Catabolism: breakdown of molecules, releases energy
• Anabolism: synthesis of molecules, requires energy
• Coupled through ATP/ADP system

ATP (Adenosine Triphosphate):

• Universal energy currency
• High-energy phosphate bonds
• Hydrolysis releases energy for cellular work
• Constantly recycled (ATP ↔ ADP + Pi)

Energy charge:

• Ratio of ATP to total adenine nucleotides
• Regulates metabolic pathways
• Maintains cellular energy balance

26. The transmission of hereditary information in the division of somatic cells. Cell cycle. Interphase Mitosis. Mitotic index. Violation of mitosis

Cell cycle phases:

• G1: cell growth, normal metabolism
• S: DNA replication
• G2: preparation for mitosis
• M: mitosis and cytokinesis

Mitosis phases:

• Prophase: chromosome condensation
• Metaphase: chromosome alignment
• Anaphase: chromosome separation
• Telophase: nuclear envelope reformation

Mitotic index: percentage of cells in mitosis Mitotic violations: nondisjunction, chromosome breaks, spindle defects

27. Direct cell division: amitosis. K-mitosis, endomitosis, polytene

Amitosis:

• Direct nuclear division without spindle formation
• Occurs in some differentiated cells
• Less precise than mitosis

K-mitosis: mitosis with spindle damage, leads to polyploidy Endomitosis: DNA replication without cell division Polytene: multiple DNA replications creating giant chromosomes

28. Meiosis, its biological significance and cytological and cytogenetic characteristics: reduction of the number of chromosomes, conjugation, crossing over, random divergence of chromosomes in daughter cells

Meiosis I:

• Prophase I: chromosome pairing, crossing over
• Metaphase I: bivalent alignment
• Anaphase I: homolog separation
• Telophase I: nuclear division

Meiosis II: similar to mitosis, sister chromatids separate

Biological significance:

• Reduces chromosome number by half
• Increases genetic diversity
• Essential for sexual reproduction

Key processes:

• Chromosome reduction (diploid → haploid)
• Crossing over creates new gene combinations
• Independent assortment increases variation

29. Asexual reproduction, its species and biological significance

Types of asexual reproduction:

• Binary fission: bacteria, protozoans
• Budding: yeast, hydra
• Fragmentation: planarians
• Vegetative propagation: plants
• Parthenogenesis: some animals

Biological significance:

• Rapid population growth
• No need for mate finding
• Preserves successful genotypes
• Colonization of new environments

30. The biological significance and essence of sexual reproduction, its types

Essence: combination of genetic material from two parents

Types:

• Isogamy: gametes of equal size
• Anisogamy: gametes of different sizes
• Oogamy: large egg, small sperm

Biological significance:

• Increases genetic diversity
• Allows adaptation to changing environments
• Reduces harmful mutations through recombination
• Promotes evolution

31. Irregular types of sexual reproduction

Types:

• Parthenogenesis: development from unfertilized egg
• Gynogenesis: sperm activates egg but doesn't contribute genes
• Androgenesis: only paternal chromosomes develop
• Hybridogenesis: alternating sexual and asexual reproduction
• Hermaphroditism: both male and female reproductive organs

32. Biological aspects of human reproduction

Female reproductive system:

• Ovaries: produce eggs and hormones
• Fallopian tubes: egg transport, fertilization site
• Uterus: embryo development
• Vagina: birth canal

Male reproductive system:

• Testes: produce sperm and hormones
• Epididymis: sperm maturation
• Vas deferens: sperm transport
• Penis: sperm delivery

Reproductive cycle:

• Menstrual cycle: 28-day average
• Ovulation: egg release
• Fertilization: sperm-egg fusion
• Pregnancy: 9-month development

33. Sexual dimorphism: genetic, morphophysiological, endocrine and behavioral aspects

Genetic aspects:

• XY (male) vs XX (female) chromosome systems
• Sex-linked genes
• Dosage compensation

Morphophysiological aspects:

• Size differences
• Body composition
• Reproductive anatomy
• Secondary sexual characteristics

Endocrine aspects:

• Testosterone in males
• Estrogen and progesterone in females
• Hormonal regulation of reproduction

Behavioral aspects:

• Mating behaviors
• Parental care
• Territorial behaviors
• Social interactions

34. Morphological structure of chromosomes. Karyotype

Chromosome structure:

• Chromatids: two identical DNA molecules
• Centromere: constriction point
• Kinetochore: protein complex at centromere
• Telomeres: chromosome ends
• Arms: p (short) and q (long)

Karyotype:

• Complete set of chromosomes
• Arranged by size and shape
• Human: 46 chromosomes (23 pairs)
• Used for genetic analysis

35. The genetic nature of sexual reproduction. The formation of germ cells (gametogenesis). Fertilization

Gametogenesis:

• Spermatogenesis: sperm formation in testes
• Oogenesis: egg formation in ovaries
• Both involve mitotic and meiotic divisions

Fertilization:

• Sperm penetrates egg
• Nuclear fusion creates zygote
• Restores diploid chromosome number
• Triggers embryonic development

36. Mendelating traits of a person

Examples of Mendelian traits in humans:

• ABO blood groups
• Rh factor
• Huntington's disease
• Cystic fibrosis
• Sickle cell anemia
• Phenylketonuria (PKU)
• Albinism
• Widow's peak hairline

37. Inheritance of traits with complete and incomplete dominance and coding

Complete dominance:

• Dominant allele masks recessive allele
• Heterozygote shows dominant phenotype
• Example: brown eyes (B) over blue eyes (b)

Incomplete dominance:

• Neither allele is completely dominant
• Heterozygote shows intermediate phenotype
• Example: red × white flowers = pink flowers

Codominance:

• Both alleles expressed simultaneously
• Example: ABO blood groups (IA and IB)

38. The laws of G. Mendel. Types and variants of inheritance of traits controlled by nuclear genes

Mendel's Laws:

1. Law of Segregation: alleles separate during gamete formation
2. Law of Independent Assortment: genes on different chromosomes assort independently
3. Law of Dominance: dominant alleles mask recessive alleles

Types of inheritance:

• Autosomal dominant
• Autosomal recessive
• X-linked dominant
• X-linked recessive
• Y-linked
• Mitochondrial inheritance

39. Crossbreeding, analyzing crossbreeding, their use in genetics

Test cross: crossing individual with unknown genotype to homozygous recessive Backcross: crossing F1 with one of the parents Reciprocal cross: switching male and female parents

Uses:

• Determine genotype of unknown individual
• Study inheritance patterns
• Confirm genetic hypotheses
• Breeding programs

40. Independent inheritance of characters in polyhybrid crosses. 3rd law of G. Mendel

Independent assortment: genes on different chromosomes segregate independently

Polyhybrid cross: involves multiple traits

• Dihybrid: 2 traits (9:3:3:1 ratio)
• Trihybrid: 3 traits (more complex ratios)

Mathematical basis:

• Each trait follows Mendelian ratios
• Combined probability = product of individual probabilities

41. Multiple allelism. Inheritance of blood groups in humans in the ABO system

Multiple allelism: more than two alleles for a single gene

ABO blood groups:

• Three alleles: IA, IB, i
• IA and IB are codominant
• i is recessive to both IA and IB
• Phenotypes: A, B, AB, O
• Genotypes: IAIA/IAi, IBIB/IBi, IAIB, ii

42. The statistical nature of the splitting

Statistical principles:

• Mendelian ratios are probabilities
• Large sample sizes approach expected ratios
• Small samples show deviation from expected ratios
• Chi-square test evaluates goodness of fit

Factors affecting ratios:

• Sample size
• Genetic linkage
• Environmental factors
• Survival differences

43. Inheritance of characters in the interaction of non-allelic genes: complementarity, epistasis, polymerization. Pleiotropy and the modifying effect of genes

Gene interactions:

• Complementarity: two genes needed for trait expression
• Epistasis: one gene masks another gene's expression
• Polymerization: multiple genes contribute to single trait

Pleiotropy: one gene affects multiple traits Modifier genes: genes that modify expression of other genes

44. Linked inheritance. Law of T. Morgan. Genetic mapping methods. Somatic hybridization, its importance in establishing human linking groups

Linkage: genes on same chromosome tend to be inherited together

Morgan's Law: recombination frequency is proportional to distance between genes

Genetic mapping:

• Recombination frequency = map distance
• 1 map unit = 1% recombination
• Chromosome maps show gene order

Somatic hybridization: fusion of somatic cells to study gene linkage

45. Types of sex determination. Types of chromosome sex determination. Inheritance of sex-linked traits

Sex determination systems:

• XY system: mammals
• ZW system: birds
• XO system: some insects
• Environmental: temperature, nutrition

Sex-linked inheritance:

• X-linked: genes on X chromosome
• Y-linked: genes on Y chromosome
• Examples: colorblindness, hemophilia

46. Proof of the leading role of DNA in heredity. Transformation and transduction

Historical evidence:

• Griffith's transformation experiments
• Avery, MacLeod, and McCarty's biochemical proof
• Hershey and Chase's bacteriophage experiments

Transformation: uptake of DNA from environment Transduction: DNA transfer via viruses

Both processes demonstrate DNA as hereditary material.

47. The structure, localization and function of nucleic acids

DNA structure:

• Double helix
• Antiparallel strands
• Base pairing: A-T, G-C
• Deoxyribose sugar

RNA structure:

• Single strand
• Ribose sugar
• Base pairing: A-U, G-C

Localization:

• DNA: nucleus, mitochondria, chloroplasts
• RNA: nucleus, cytoplasm, ribosomes

Functions:

• DNA: genetic information storage
• RNA: protein synthesis, regulation

48. RNA types and their role in cell protein synthesis

mRNA (messenger RNA):

• Carries genetic code from DNA
• Template for protein synthesis
• Codons specify amino acids

tRNA (transfer RNA):

• Brings amino acids to ribosome
• Anticodon pairs with mRNA codon
• Amino acid attachment site

rRNA (ribosomal RNA):

• Structural component of ribosomes
• Catalyzes peptide bond formation
• Several types (18S, 28S, 5.8S, 5S)

49. The genetic code. The main properties of the genetic code. Decryption of the genetic code in the process of protein synthesis in the cell

Genetic code properties:

• Triplet: three bases code for one amino acid
• Universal: same code in all organisms
• Degenerate: multiple codons for same amino acid
• Non-overlapping: codons read sequentially
• Comma-free: no punctuation between codons

Decryption process:

• mRNA codons read by ribosome
• tRNA anticodons pair with codons
• Amino acids joined in sequence
• Start codon (AUG) and stop codons (UAA, UAG, UGA)

50. Genetic engineering. Synthesis and isolation of genes. Plasmids. Genetic engineering advances in medicine

Genetic engineering: manipulation of genetic material

Techniques:

• Gene cloning
• PCR amplification
• DNA sequencing
• Gene synthesis
• Restriction enzymes
• Plasmid vectors

Medical applications:

• Recombinant proteins (insulin, growth hormone)
• Gene therapy
• Vaccine development
• Diagnostic tests
• Personalized medicine

51. The modern concept of the gene as a functional unit of heredity and variability. Regulator gene, operon, operator gene, structural genes

Modern gene concept:

• DNA sequence coding for functional product
• Can be protein-coding or regulatory
• Includes exons and introns
• Regulatory sequences control expression

Operon structure (prokaryotes):

• Structural genes: code for enzymes
• Operator: regulatory sequence
• Promoter: RNA polymerase binding site
• Regulator gene: codes for repressor protein

52. Implementation of genetic information: transcription, post-transcriptional processes (processing and splicing)

Transcription:

• DNA → RNA synthesis
• RNA polymerase enzyme
• Promoter, elongation, termination

Post-transcriptional processing (eukaryotes):

• 5' capping: modified guanosine cap
• 3' polyadenylation: poly-A tail
• Splicing: intron removal, exon joining
• Alternative splicing: different mRNA variants

53. Unique DNA properties: replication and repair

DNA replication:

• Semi-conservative mechanism
• DNA polymerase enzyme
• Leading and lagging strands
• Proofreading function

DNA repair mechanisms:

• Mismatch repair: corrects replication errors
• Base excision repair: removes damaged bases
• Nucleotide excision repair: removes bulky lesions
• Double-strand break repair: fixes chromosome breaks

54. Cytoplasmic genes and their role in cytoplasmic heredity

Cytoplasmic genes:

• Mitochondrial DNA
• Chloroplast DNA (plants)
• Maternal inheritance pattern
• Encode essential proteins

Characteristics:

• Circular DNA molecules
• Own genetic code variations
• Maternally inherited
• High mutation rates

Role in heredity:

• Metabolic functions
• Some genetic diseases
• Evolutionary significance

55. Genetically modified objects. Their biomedical significance

Types of GMOs:

• Transgenic animals
• Genetically modified plants
• Engineered microorganisms
• Cell lines

Biomedical applications:

• Disease models
• Pharmaceutical production
• Organ transplantation
• Gene therapy vectors
• Diagnostic tools

56. The use of genetic information in the process of life: translation, stages of protein biosynthesis

Translation stages:

1. Initiation: ribosome assembly, start codon recognition
2. Elongation: amino acid addition, peptide bond formation
3. Termination: stop codon recognition, protein release

Key components:

• mRNA template
• tRNA adapters
• Ribosomal machinery
• Amino acids
• Energy (GTP)

57. Features of the organization of the genome of prokaryotes

Prokaryotic genome features:

• Circular chromosome
• No histones (except archaea)
• Genes organized in operons
• No introns in most genes
• Polycistronic mRNA
• Coupled transcription-translation

58. Features of expression in prokaryotes

Prokaryotic gene expression:

• Direct translation of mRNA
• No post-transcriptional modification
• Rapid response to environmental changes
• Operon regulation
• Riboswitches and small RNAs

59. Methods of studying DNA. Genome sequencing. Modern genomics

DNA study methods:

• PCR amplification
• Restriction enzyme analysis
• DNA sequencing
• Southern blotting
• Chromosome walking

Genome sequencing:

• Sanger sequencing
• Next-generation sequencing
• Whole genome shotgun

Modern genomics:

• Comparative genomics
• Functional genomics
• Pharmacogenomics
• Personalized medicine

60. Regulation of protein synthesis in the cell of prokaryotes according to Jacob and Mono

Lac operon model:

• Negative control by repressor
• Positive control by CAP-cAMP
• Inducible system

Trp operon model:

• Repressible system
• Attenuation mechanism
• Feedback regulation

General principles:

• Operons coordinate gene expression
• Regulatory proteins control transcription
• Metabolic efficiency

61. Mutation variation. The mutational theory of Hugo de Vries. The law of homological series in hereditary variation N.N. Vavilova. Spontaneous and induced mutations. Classification of mutations

Mutational theory (Hugo de Vries):

• Mutations are sudden heritable changes
• Source of evolutionary novelty
• Occur randomly and spontaneously
• Provide raw material for natural selection

Vavilov's Law of Homologous Series:

• Related species show similar patterns of variation
• Homologous genes produce similar mutations
• Predictable mutation spectrum within taxonomic groups

Types of mutations:

• Spontaneous: occur naturally (10⁻⁶ to 10⁻¹⁰ per base pair per generation)
• Induced: caused by external factors (mutagens)

Classification:

• By scale: point mutations, chromosomal aberrations, genomic mutations
• By effect: silent, missense, nonsense, frameshift
• By cell type: somatic, germinal

62. Chromosomal aberrations, their types. The importance of chromosomal aberrations in variability

Types of chromosomal aberrations:

• Deletions: loss of chromosome segment
• Duplications: extra copy of chromosome segment
• Inversions: reversal of chromosome segment
• Translocations: transfer between non-homologous chromosomes
• Ring chromosomes: circular chromosome formation

Mechanisms:

• Unequal crossing over
• Chromosome breakage and rejoining
• Replication errors

Importance in variability:

• Create new gene combinations
• Alter gene expression levels
• Provide evolutionary raw material
• Can cause genetic diseases

63. Point mutations. Cell repair systems

Point mutations:

• Transitions: purine to purine (A↔G) or pyrimidine to pyrimidine (C↔T)
• Transversions: purine to pyrimidine or vice versa
• Insertions/deletions: addition or removal of nucleotides

Effects:

• Silent: no amino acid change
• Missense: amino acid change
• Nonsense: premature stop codon
• Frameshift: reading frame alteration

DNA repair systems:

• Proofreading: 3' to 5' exonuclease activity
• Mismatch repair: corrects replication errors
• Base excision repair: removes damaged bases
• Nucleotide excision repair: removes bulky lesions
• Homologous recombination: repairs double-strand breaks

64. Induced mutagenesis and the concept of mutagens

Mutagens:

• Physical: UV radiation, X-rays, gamma rays
• Chemical: base analogs, alkylating agents, intercalating agents
• Biological: transposons, viruses

Mutagenic mechanisms:

• DNA damage induction
• Replication error promotion
• Repair system interference

Applications:

• Mutation breeding in agriculture
• Laboratory research
• Cancer therapy
• Genetic screening

65. Multiple allelism, inheritance of characters and the interaction of alleles in multiple allelism

Multiple allelism: more than two alleles for a single gene in a population

Examples:

• ABO blood groups (IA, IB, i)
• HLA system (hundreds of alleles)
• Coat color in rabbits (C, cch, ch, c)

Allele interactions:

• Complete dominance: one allele masks others
• Incomplete dominance: blended phenotype
• Codominance: both alleles expressed
• Recessive: masked by dominant alleles

66. Modification variability. Reaction norm. Methods for studying modification variability

Modification variability:

• Non-heritable changes in phenotype
• Response to environmental factors
• Same genotype, different phenotypes

Reaction norm:

• Range of phenotypes possible for a genotype
• Genetic limits of environmental response
• Phenotypic plasticity

Study methods:

• Controlled environment experiments
• Twin studies
• Transplant experiments
• Statistical analysis
• Molecular markers

67. Features of a person as an object of genetic research, his biosocial nature

Genetic research challenges:

• Long generation time
• Small family size
• Ethical constraints
• Complex traits
• Environmental influences

Biosocial nature:

• Biological inheritance
• Cultural transmission
• Gene-environment interactions
• Social behavior evolution
• Language and learning

Special considerations:

• Ethical guidelines
• Informed consent
• Privacy protection
• Psychological impact
• Social implications

68. Human genetic polymorphism. Mutations and their role in the development of diseases

Genetic polymorphism:

• Multiple alleles in population
• Balanced polymorphism
• Neutral variation
• Adaptive significance

Disease-causing mutations:

• Monogenic disorders: single gene defects
• Polygenic disorders: multiple gene involvement
• Chromosomal disorders: structural abnormalities
• Mitochondrial disorders: maternal inheritance

Examples:

• Sickle cell anemia (point mutation)
• Huntington's disease (repeat expansion)
• Down syndrome (trisomy 21)
• Duchenne muscular dystrophy (deletion)

69. The role of heredity and environment in the formation of a normal and pathologically altered human phenotype. Human hereditary diseases: chromosomal, gene, diseases with a hereditary predisposition. Multifactorial diseases

Heredity vs. Environment:

• Genetic component: heritability
• Environmental component: modifiability
• Gene-environment interactions
• Epigenetic modifications

Types of hereditary diseases:

• Chromosomal: Down syndrome, Turner syndrome
• Monogenic: cystic fibrosis, phenylketonuria
• Multifactorial: diabetes, heart disease, cancer
• Mitochondrial: Leber's optic neuropathy

Multifactorial diseases:

• Multiple genes involved
• Environmental triggers
• Threshold effects
• Familial clustering

70. The biosocial nature of man. Methods of human genetics and their characteristics. Cytogenetic method, its essence and capabilities

Biosocial nature:

• Biological evolution
• Cultural evolution
• Social behavior
• Language development
• Tool use

Cytogenetic method:

• Chromosome analysis
• Karyotype construction
• Banding techniques
• FISH (Fluorescent In Situ Hybridization)

Capabilities:

• Detect chromosomal abnormalities
• Identify structural rearrangements
• Diagnose genetic syndromes
• Prenatal diagnosis

71. The genealogical method of studying the inheritance of traits in humans. Compilation and analysis of genealogical trees

Genealogical method:

• Family tree construction
• Pedigree analysis
• Inheritance pattern determination
• Risk assessment

Pedigree symbols:

• Males: squares
• Females: circles
• Affected individuals: filled symbols
• Carriers: half-filled symbols
• Deceased: diagonal line

Analysis:

• Dominant vs. recessive patterns
• Sex-linked inheritance
• Consanguinity effects
• Penetrance and expressivity

72. Human genetics. Population-statistical method

Population-statistical method:

• Large population studies
• Allele frequency calculations
• Hardy-Weinberg equilibrium
• Association studies

Applications:

• Disease prevalence
• Genetic diversity
• Population structure
• Evolutionary studies

Statistical tools:

• Chi-square tests
• Regression analysis
• Linkage analysis
• Genome-wide association studies (GWAS)

73. Human genetics. The twin method, essence and meaning

Twin method:

• Compare identical vs. fraternal twins
• Separate genetic and environmental factors
• Heritability estimation

Types of studies:

• Concordance studies
• Twin-family studies
• Adoption studies
• Twins reared apart

Heritability calculation:

• h² = (MZ concordance - DZ concordance) / (100 - DZ concordance)
• Range: 0 (no genetic influence) to 1 (complete genetic determination)

74. The genetic structure of the Mendelian population. Hardy-Weinberg Law

Mendelian population:

• Interbreeding group
• Common gene pool
• Shared allele frequencies
• Genetic equilibrium

Hardy-Weinberg Law:

• Allele frequencies remain constant
• Genotype frequencies: p² + 2pq + q² = 1
• Conditions: large population, random mating, no selection, no migration, no mutation

Applications:

• Population genetics
• Disease frequency prediction
• Evolutionary studies
• Conservation genetics

75. Morphofunctional characterization and classification of chromosomes. Karyotype of a person. Cytogenetic method. Denver and Paris nomenclature of the human karyotype

Chromosome classification:

• Metacentric: centromere in middle
• Submetacentric: centromere off-center
• Acrocentric: centromere near end
• Telocentric: centromere at end

Human karyotype: 46,XY (male) or 46,XX (female)

Nomenclature systems:

• Denver system: groups A-G by size
• Paris system: numerical 1-22 plus sex chromosomes
• ISCN: International System for Cytogenetic Nomenclature

76. The subject and history of embryology. Preformism and epigenesis

Embryology: study of embryonic development

Historical theories:

• Preformism: miniature organism pre-exists in gamete
• Epigenesis: gradual development from undifferentiated material

Modern understanding:

• Combination of both concepts
• Genetic program (preformation)
• Environmental interactions (epigenesis)
• Developmental plasticity

77. Ontogenesis. Periodization of ontogenesis. Modifications of ontogenesis: embryonization, diapause, neoteny

Ontogenesis: individual development from fertilization to death

Periodization:

• Embryonic period: fertilization to birth
• Postnatal period: birth to death
• Reproductive period: sexual maturity
• Senescence: aging and death

Modifications:

• Embryonization: increased embryonic development
• Diapause: developmental arrest
• Neoteny: retention of juvenile characteristics

78. Gametogenesis. Spermatogenesis. Oogenesis, structural features of germ cells

Spermatogenesis:

• Mitotic phase: spermatogonial proliferation
• Meiotic phase: reduction division
• Differentiation phase: sperm maturation
• Duration: ~74 days

Oogenesis:

• Mitotic phase: oogonial proliferation
• Growth phase: oocyte enlargement
• Maturation phase: meiotic divisions
• Duration: months to years

Gamete structure:

• Sperm: head (nucleus, acrosome), midpiece (mitochondria), tail (flagellum)
• Egg: large cytoplasm, cortical granules, zona pellucida

79. The genetic nature of fertilization. Fertilization disorders, irregular types of fertilization

Fertilization process:

• Sperm capacitation
• Acrosome reaction
• Sperm-egg binding
• Cortical reaction
• Nuclear fusion

Disorders:

• Polyspermy: multiple sperm entry
• Parthenogenesis: development without fertilization
• Hybridization: cross-species fertilization

Irregular types:

• Artificial insemination
• In vitro fertilization
• Intracytoplasmic sperm injection

80. Fertilization and ooplasmic segregation

Ooplasmic segregation:

• Unequal distribution of cytoplasmic components
• Maternal factors determine cell fate
• Morphogenetic gradients
• Axis establishment

Significance:

• Early embryonic patterning
• Cell fate determination
• Developmental regulation
• Species-specific patterns

81. Blastulation. Blastulation disorders

Blastulation:

• Rapid cell divisions
• Blastocyst formation
• Cavity (blastocoel) formation
• Cell differentiation begins

Key events:

• Compaction
• Polarization
• Cavitation
• Lineage segregation

Disorders:

• Abnormal cell division
• Implantation failure
• Developmental arrest
• Chromosomal abnormalities

82. Gastrulation and organogenesis. Possible disorders

Gastrulation:

• Formation of three germ layers
• Ectoderm, mesoderm, endoderm
• Morphogenetic movements
• Axis establishment

Organogenesis:

• Organ formation from germ layers
• Induction and differentiation
• Pattern formation
• Morphogenesis

Disorders:

• Neural tube defects
• Congenital heart defects
• Cleft palate
• Limb malformations

83. Differentiation and integration in development. Anomalies and malformations

Differentiation:

• Cell specialization
• Gene expression changes
• Morphological changes
• Functional maturation

Integration:

• Coordinate development
• Cell-cell communication
• Tissue interactions
• Organ system formation

Anomalies:

• Genetic defects
• Environmental factors
• Developmental timing errors
• Teratogenic effects

84. The role of heredity and environment in ontogenesis

Hereditary factors:

• Genetic program
• Developmental genes
• Regulatory networks
• Epigenetic modifications

Environmental factors:

• Nutrition
• Temperature
• Chemicals
• Radiation
• Infections

Interactions:

• Gene-environment interactions
• Sensitive periods
• Phenotypic plasticity
• Adaptive responses

85. The mechanisms of ontogenesis at the cellular and organismic levels: reproduction, growth, differentiation, morphogenesis

Cellular level:

• Reproduction: mitosis, meiosis
• Growth: cell enlargement, protein synthesis
• Differentiation: gene expression changes
• Morphogenesis: cell shape changes, migration

Organismic level:

• Reproduction: gamete formation, fertilization
• Growth: tissue and organ enlargement
• Differentiation: organ specialization
• Morphogenesis: body plan formation

86. Postnatal ontogenesis

Phases:

• Neonatal period: birth to 28 days
• Infancy: 28 days to 1 year
• Childhood: 1 year to puberty
• Adolescence: puberty to adulthood
• Adulthood: reproductive maturity
• Senescence: aging and decline

Characteristics:

• Continued growth and development
• Organ maturation
• Behavioral development
• Reproductive maturation
• Aging processes

87. Biological aging at various levels of organism organization. Problems of longevity

Levels of aging:

• Molecular: protein damage, DNA mutations
• Cellular: senescence, apoptosis
• Tissue: loss of function, fibrosis
• Organ: decreased efficiency
• Organismic: death

Aging theories:

• Free radical theory
• Telomere shortening
• Genetic program
• Wear and tear
• Hormonal changes

Longevity factors:

• Genetics
• Lifestyle
• Environment
• Medical care
• Nutrition

88. Regeneration of organs and tissues, physiological and reparative regeneration

Types of regeneration:

• Physiological: normal tissue replacement
• Reparative: healing after injury
• Compensatory: growth after loss

Mechanisms:

• Stem cell activation
• Cell proliferation
• Tissue remodeling
• Scar formation

Factors affecting regeneration:

• Age
• Tissue type
• Extent of damage
• Blood supply
• Nutrition

89. Phylogenesis of organ systems of Chordates

Nervous system:

• Neural tube formation
• Brain regionalization
• Complexity increase
• Behavioral sophistication

Circulatory system:

• Single to double circulation
• Heart chamber evolution
• Vessel specialization
• Pressure regulation

Respiratory system:

• Gills to lungs
• Air sac development
• Breathing mechanisms
• Gas exchange efficiency

Digestive system:

• Gut differentiation
• Enzyme specialization
• Absorption optimization
• Symbiotic relationships

90. Transplantation of embryos. Allophenic animals

Embryo transplantation:

• Nuclear transfer
• Embryo splitting
• Blastocyst transfer
• Reproductive cloning

Allophenic animals:

• Chimeric organisms
• Mixed cell populations
• Developmental studies
• Fate mapping

Applications:

• Research models
• Agricultural breeding
• Conservation efforts
• Medical applications

91. Organ and tissue transplantation, tissue incompatibility

Transplantation types:

• Autograft: within same individual
• Allograft: between individuals of same species
• Xenograft: between different species
• Isograft: between genetically identical individuals

Tissue incompatibility:

• MHC (Major Histocompatibility Complex) differences
• Immune rejection
• Graft-versus-host disease
• Immunosuppression needs

92. The concept of homeostasis. Genetic, cellular, and systemic foundations of homeostatic reactions of a multicellular organism

Homeostasis: maintenance of stable internal environment

Genetic basis:

• Regulatory genes
• Feedback mechanisms
• Adaptation genes
• Stress response genes

Cellular basis:

• Membrane transport
• Enzymatic regulation
• Signal transduction
• Cellular communication

Systemic basis:

• Nervous system control
• Endocrine regulation
• Immune system
• Circulatory system

93. Immunological mechanisms of homeostasis. Transplant problems

Immune homeostasis:

• Self vs. non-self recognition
• Immune tolerance
• Inflammatory responses
• Immune memory

Transplant immunology:

• Tissue typing
• Immunosuppression
• Tolerance induction
• Rejection prevention

Clinical applications:

• Organ transplantation
• Bone marrow transplantation
• Tissue engineering
• Regenerative medicine

94. Immunological incompatibility. Rhesus conflict

Rhesus system:

• Rh+ and Rh- phenotypes
• Genetic basis: RhD gene
• Inheritance pattern: dominant/recessive

Rhesus conflict:

• Rh- mother, Rh+ fetus
• Maternal antibody production
• Hemolytic disease of newborn
• Prevention: RhoGAM injection

Clinical management:

• Prenatal screening
• Antibody monitoring
• Fetal assessment
• Treatment options

95. Parasitism as a biological phenomenon. Adaptations to parasitism. Interaction in the host parasite system. The evolution of parasitism under the influence of an anthropogenic factor

Parasitism: relationship where one organism benefits at expense of another

Parasite adaptations:

• Attachment structures
• Immune evasion
• Reproductive strategies
• Host specificity
• Life cycle complexity

Host-parasite interactions:

• Coevolution
• Arms race
• Tolerance vs. resistance
• Population dynamics

Anthropogenic influences:

• Habitat destruction
• Climate change
• Pollution
• Emerging diseases
• Zoonotic transmission

96. Type Protozoa. Class Sarcoda. Importance for medicine

Class Sarcoda characteristics:

• Amoeboid movement
• Pseudopodia formation
• Phagocytic feeding
• Asexual reproduction

Medically important species:

• Entamoeba histolytica: amebic dysentery
• Acanthamoeba: keratitis, encephalitis
• Naegleria fowleri: primary amoebic meningoencephalitis

Disease characteristics:

• Intestinal infections
• Tissue invasion
• Central nervous system involvement
• Opportunistic infections

97. Type Protozoa. Class Flagellum. Importance for medicine

Class Flagellata characteristics:

• Flagellar locomotion
• Diverse feeding strategies
• Complex life cycles
• Sexual and asexual reproduction

Medically important species:

• Trypanosoma: sleeping sickness, Chagas disease
• Leishmania: leishmaniasis
• Giardia: giardiasis
• Trichomonas: trichomoniasis

Disease transmission:

• Vector-borne (insects)
• Waterborne
• Sexual transmission
• Zoonotic cycles

98. Type Protozoa. Class Apicomplexa. Importance for medicine

Class Apicomplexa characteristics:

• Apical complex for host invasion
• Obligate parasites
• Complex life cycles
• Alternating hosts

Medically important species:

• Plasmodium: malaria
• Toxoplasma gondii: toxoplasmosis
• Cryptosporidium: cryptosporidiosis
• Cyclospora: cyclosporiasis

Disease impact:

• Global health burden
• Mortality and morbidity
• Economic consequences
• Drug resistance

99. Type Protozoa. Class Ciliates. Importance for medicine

Class Ciliata characteristics:

• Ciliary locomotion
• Complex cellular organization
• Conjugation (sexual process)
• Diverse ecological roles

Medically important species:

• Balantidium coli: balantidiasis
• Stentor: rare infections
• Paramecium: laboratory infections

Clinical significance:

• Rare human pathogens
• Opportunistic infections
• Laboratory contaminants
• Research models

100. Type Plathelminthes. Class Trematoda. Importance for medicine

Class Trematoda characteristics:

• Flattened body
• Oral and ventral suckers
• Complex life cycles
• Hermaphroditic (mostly)

Medically important species:

• Schistosoma: schistosomiasis
• Fasciola: fascioliasis
• Clonorchis: clonorchiasis
• Paragonimus: paragonimiasis

Disease characteristics:

• Chronic infections
• Organ damage
• Inflammatory responses
• Carcinogenic potential

101. Type Plathelminthes. Class Cestoda. Importance for medicine

Class Cestoda characteristics:

• Segmented body (proglottids)
• Scolex with attachment organs
• No digestive system
• Hermaphroditic

Medically important species:

• Taenia solium: pork tapeworm, cysticercosis
• Taenia saginata: beef tapeworm
• Diphyllobothrium: fish tapeworm
• Echinococcus: hydatid disease

Disease manifestations:

• Intestinal infections
• Tissue cysts
• Neurological symptoms
• Nutritional deficiencies

102. Type Nemathelminthes. Importance for medicine

Nemathelminthes characteristics:

• Cylindrical body
• Complete digestive system
• Separate sexes
• Diverse life cycles

Medically important species:

• Ascaris lumbricoides: ascariasis
• Enterobius vermicularis: pinworm
• Trichuris trichiura: whipworm
• Ancylostoma/Necator: hookworm
• Wuchereria bancrofti: lymphatic filariasis

Disease impact:

• Intestinal obstruction
• Nutritional deficiencies
• Allergic reactions
• Tissue damage

103. Ovogelmintoskopiya. Methods of coprological analysis

Ovogelmintoskopiya: microscopic examination of eggs and larvae

Methods:

• Direct smear: simple microscopic examination
• Concentration methods: sedimentation, flotation
• Quantitative methods: egg counting
• Cultivation: larval identification

Applications:

• Diagnosis of helminth infections
• Species identification
• Infection intensity assessment
• Treatment monitoring

104. Type Arthropods. Class Arachnids. Importance for medicine

Class Arachnida characteristics:

• Eight legs
• Two body segments
• Chelicerae and pedipalps
• No antennae

Medically important species:

• Ixodes: Lyme disease, tick-borne encephalitis
• Dermacentor: Rocky Mountain spotted fever
• Sarcoptes scabiei: scabies
• Demodex: demodicosis

Disease transmission:

• Vector-borne diseases
• Direct parasitism
• Allergic reactions
• Envenomation

105. Type Arthropods. Class Insects. Importance for medicine

Class Insecta characteristics:

• Six legs
• Three body segments
• Wings (usually)
• Metamorphosis

Medically important species:

• Anopheles: malaria transmission
• Aedes: dengue, Zika, yellow fever
• Culex: West Nile virus
• Glossina: sleeping sickness
• Phlebotomus: leishmaniasis

Disease transmission:

• Vector-borne diseases
• Mechanical transmission
• Allergic reactions
• Myiasis

106. The essence of evolution. Micro- and macroevolution. Characterization of mechanisms and main results

Evolution: change in gene frequencies over time

Microevolution:

• Changes within populations
• Gene frequency changes
• Adaptation to environment
• Speciation beginnings

Macroevolution:

• Changes above species level
• Major morphological changes
• Evolutionary radiations
• Extinction events

Mechanisms:

• Natural selection
• Genetic drift
• Gene flow
• Mutation

107. The biological species and its definition. Criteria of species

Species definition: groups of interbreeding populations reproductively isolated from other groups

Species criteria:

• Morphological: structural similarities
• Biological: reproductive compatibility
• Ecological: environmental adaptation
• Genetic: genetic similarity
• Phylogenetic: evolutionary relationships

Species problems:

• Asexual organisms
• Extinct species
• Geographically separated populations
• Chronospecies

108. Population as an elementary unit of evolution

Population: group of interbreeding individuals

Population genetics:

• Gene pool
• Allele frequencies
• Hardy-Weinberg equilibrium
• Genetic drift

Evolutionary factors:

• Mutation
• Selection
• Gene flow
• Drift
• Inbreeding

109. Elementary evolutionary factors

Mutation:

• Ultimate source of variation
• Usually deleterious
• Balanced by selection
• Provides evolutionary potential

Selection:

• Directional, stabilizing, disruptive
• Fitness differences
• Adaptation mechanism
• Can be natural or sexual

Gene flow:

• Migration between populations
• Homogenizes allele frequencies
• Opposes local adaptation
• Maintains species cohesion

Genetic drift:

• Random sampling effects
• Stronger in small populations
• Causes allele frequency changes
• Can override weak selection

110. Microevolutionary processes in human populations

Human population genetics:

• Founder effects
• Population bottlenecks
• Migration patterns
• Admixture events

Examples:

• Sickle cell anemia frequency
• Lactose tolerance evolution
• High altitude adaptations
• Disease resistance alleles

Factors:

• Cultural practices
• Medical interventions
• Population size changes
• Geographic isolation

111. The origin of life and the evolution of the organic world

Origin of life theories:

• Chemical evolution
• RNA world hypothesis
• Metabolism-first theories
• Panspermia

Major evolutionary events:

• Prokaryote evolution
• Eukaryote origin
• Multicellularity
• Cambrian explosion
• Mass extinctions

Evidence:

• Fossil record
• Molecular phylogenies
• Comparative anatomy
• Biogeography

112. Natural selection. The specificity of the action of natural selection in human populations

Natural selection types:

• Directional: favors one extreme
• Stabilizing: favors intermediate phenotypes
• Disruptive: favors extreme phenotypes
• Balancing: maintains variation

Human-specific factors:

• Cultural evolution
• Medical interventions
• Technological changes
• Social structures

Examples:

• Disease resistance
• Dietary adaptations
• Cognitive abilities
• Reproductive strategies

113. The relationship between ontogenesis and phylogenesis. Biogenetic law

Biogenetic law: "ontogeny recapitulates phylogeny"

Modern understanding:

• Developmental constraints
• Evolutionary conservation
• Heterochrony
• Developmental systems drift

Examples:

• Embryonic gill slits
• Limb development
• Gene expression patterns
• Morphological sequences

114. The origin of man

Human evolution timeline:

• Primate ancestors
• Australopithecus
• Homo habilis
• Homo erectus
• Homo sapiens

Key adaptations:

• Bipedalism
• Brain enlargement
• Tool use
• Language development
• Cultural evolution

Evidence:

• Fossil record
• Comparative anatomy
• Molecular phylogenies
• Archaeological evidence

115. Phylogenesis of organs and functional systems of chordates

Nervous system evolution:

• Neural tube formation
• Brain regionalization
• Complexity increase
• Behavioral sophistication

Circulatory system evolution:

• Single to double circulation
• Heart chamber evolution
• Blood pressure regulation
• Oxygen transport efficiency

Other systems:

• Respiratory: gills to lungs
• Digestive: specialization
• Excretory: kidney evolution
• Reproductive: internal fertilization

116. The concept of races and species unity of mankind

Race concepts:

• Biological variation
• Geographic populations
• Genetic clusters
• Social constructs

Species unity:

• Interfertility
• Continuous variation
• Recent common ancestry
• Genetic similarity

Modern understanding:

• Clinal variation
• Population structure
• Admixture
• Cultural differences

117. Ethical problems of medical biology and genetics

Genetic testing:

• Informed consent
• Privacy concerns
• Discrimination risks
• Psychological impact

Gene therapy:

• Safety concerns
• Equitable access
• Enhancement vs. treatment
• Germline modification

Research ethics:

• Human subjects protection
• Animal welfare
• Dual-use research
• Publication responsibilities

118. The biosphere and man. Medical aspects of environmental protection

Biosphere components:

• Atmosphere
• Hydrosphere
• Lithosphere
• Living organisms

Human impact:

• Pollution
• Climate change
• Habitat destruction
• Species extinction

Medical implications:

• Environmental diseases
• Emerging infections
• Food security
• Water quality

119. Actual issues of medical ecology. Diseases of a new type. Environmental diseases

Environmental diseases:

• Air pollution effects
• Water contamination
• Chemical exposure
• Radiation effects

Emerging diseases:

• Zoonotic spillover
• Antibiotic resistance
• Climate-related diseases
• Occupational hazards

Prevention strategies:

• Environmental monitoring
• Exposure reduction
• Public health measures
• Sustainable development

120. The doctrine of the biosphere. Noosphere

Biosphere concept (Vernadsky):

• Living matter effects
• Biogeochemical cycles
• Energy flows
• Global ecosystem

Noosphere concept:

• Sphere of human thought
• Technological impact
• Conscious evolution
• Sustainable development

Implications:

• Human responsibility
• Global stewardship
• Technological solutions
• Future evolution