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Genetics and Inheritance

  • Pea Plant Pod Color: Green (V) is dominant over yellow (v).
  • Pod Shape: Swollen (B) is dominant over constricted (b).
  • Genotype Probability: Crossing VvBb with Vvbb, the probability of yellow color is 1/4. The probability of swollen shape is 3/4.
  • Monohybrid Cross: Offspring show only one parent's character, defined as dominant.
  • Mendel's Law of Dominance: During gamete formation, alleles of a gene separate. The separation of alleles of one gene does not influence the alleles of another gene.

Cell Biology

  • Structural and Functional Unit: The cell.
  • Organisms Without Mitochondria: Prokaryotes.
  • Mitochondria Function: Cellular respiration occurs, waste substances are demolished, and cobalamin (Vitamin B12) synthesis occurs.

Human Anatomy and Physiology

  • Muscle Stimulation: Muscles are stimulated to contract by nerve impulses.
  • Respiratory System: Air passes through the trachea, which divides into two bronchi (right and left), each leading to a lung.
  • Atrioventricular Valves: Mitral and tricuspid valves prevent blood backflow into the atrium when the ventricle contracts.
  • Kidney Function: Secretion: Occurs mainly in the glomerulus, allows elimination of filtrate, recovers water and solutes, reintroduces them into the blood.
    • Secretion: Hippuric acid removes drugs, toxins, and ions from the blood.
  • Oxidative Phosphorylation: The energy released by electron transport pumps hydrogen ions against the gradient, which is coupled to ATP synthesis by ATP synthase.
    • Water is NOT the final electron acceptor but a byproduct.
  • Intestinal Villi Function: Absorption.
  • Muscle Tissue Structure: Striated muscles have cylindrical, multinucleated fibers with an average diameter between 10 - 100 \mu m. Myosin and actin are organized into thick and thin filaments, respectively.
  • Muscle Contraction: Requires ATP for breaking bonds between actin and myosin and for the return of Ca^{2+} ions into the sarcoplasmic reticulum. ATP is derived from phosphocreatine, cellular respiration, and glycolysis (linked to lactic fermentation depending on muscle activity duration).

Genetics and Chromosomal Abnormalities

  • Turner Syndrome: Aneuploidy.
  • Meiosis: Tetrads are formed in prophase I; division of sister chromatids occurs in anaphase II.
  • Chromosomes: Sister chromatids are joined by the centromere; homologous chromosomes are present.
  • Centromere: The location of Minisatellite DNA.
  • DNA Replication: Semi-conservative.
  • Mutation: A stable, heritable change in a cell's DNA sequence; does not always affect reproductive cells.

Biochemistry and Molecular Biology

  • Plant Hormones: Regulate plant growth; examples include auxins, gibberellins, ethylene, and abscisic acid.
  • Golgi Apparatus: Has a cis and trans side; site of lipid synthesis; contains enzymes for peroxide demolition; not typical of animals.
  • tRNA: Plays a crucial role in mRNA translation; has a cloverleaf configuration maintained by disulfide bridges; the amino acid attachment site is at the 3' end with an identical sequence (5'-CCA-3') in all tRNAs; the anticodon recognizes the corresponding codon in mRNA.
  • Calvin Cycle: Located in the stroma of chloroplasts; has the first step catalyzed by the enzyme citrate synthase; starting from CO_2.

Microbiology

  • Clostridium: Includes Botulism bacterium.
  • Streptococci: Facultative anaerobes.
  • Bacterial Cell Wall: Composed of peptidoglycan.

Evolutionary Biology

  • Bacterial Production of Human Insulin: Requires genetic modification.
  • Binomial Nomenclature: Identifies a species using two terms: genus and species.
  • Factors Leading to New Species: Divergent selection.

Blood and Circulation

  • Platelets: Derived from megakaryocytes; have an average lifespan of about 10 days; smallest figurative elements of the blood; do not have a nucleus.
  • Atherosclerosis: Caused by cholesterol deposits in the inner wall of the arteries, which causes the hardening.

Cellular Processes

  • Apoptosis: Is the mechanism that allwos the cell to acquire free DNA.
  • Phagocytosis: Is the mechanism that occurs when a cell eats itself.

Other

  • Water-Soluble Hormones: Bind to specific receptors on target cells and trigger a chain reaction inside the cell.
  • Immunoglobulin Heavy Chains: Made up of one variable domain plus three or four constant domains.
  • Red Muscle Fibers: Poorly vascularized; have a low contraction speed and high resistance to fatigue; they do not possess myoglobin.
  • Enzymes: Enzymes are necessary for both alcoholic and to the oxidative decarboxylation of pyruvate.
  • Photosythesis: Pigments that absorb light radiation during photosynthesis do each absorb a specific wavelength.
  • Temporal Bone: Located in the skull.