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Genetic Drift and Allele Frequencies

  • In genetic drift, allele frequencies in a population change randomly over time.

FISH Investigation

  • FISH (Fluorescent In Situ Hybridization) is used to highlight chromosomal microdeletions.

Spinal Nerves

  • Spinal nerves innervate all parts of the body and are part of the somatic nervous system.

Cell Membrane Composition

  • The cell membrane does not contain peptidoglycans.
  • It contains proteins, phospholipids, cholesterol, and glycolipids.

Hardy-Weinberg Law

  • Related to population changes.

Types of Mutations

  • Point mutations: changes in a single base pair.
  • Frameshift mutations: insertions or deletions that alter the reading frame.
  • Splicing mutations: affect how introns are removed.

Chromosome Number

  • Triploidy involves 12 pairs of chromosomes.

Natural vs. Artificial Selection

  • Contrast between natural and artificial selection.

Bacilli Shape

  • Bacilli are stick-shaped bacteria.

Energy Types in Cells

  • Human cells use chemical energy to perform their functions.

Phagocytosis

  • Phagocytosis involves the formation of a phagolysosome, which is formed after the early endosome, late endosome and autophagosome.

X Chromosome Inactivation in Female Mammals

  • Female mammals are mosaics for character expression because one or the other X chromosome randomly undergoes inactivation resulting in cells with different chromosomal constitutions.

Enzyme Inhibitors

  • Enzyme inhibitors can bind to the enzyme and can compete with the substrate.

Bacterial Genes

  • Bacterial genes encoding transcription control proteins are called regulators.

Bacteria Characteristics

  • Bacteria lack a nucleus.
  • Bacteria have ribosomes.

Congenital Malformations

  • A malformation that appears in a child from birth is congenital/hereditary.

Respiratory Rate

  • Decreased blood pH causes the respiratory rate to increase.

Retrotransposons and Reverse Transcriptase

-Retrotransposons exploit the enzyme reverse transcriptase.

RNA Polymerase Function

  • RNA polymerase transcribes both exons and introns.
  • RNA polymerase synthesizes an RNA strand in the 5'-3' direction using a DNA template (not the 3'-5' direction), so the template must run in the 3'-5' orientation. Then, since the new strand is synthesized from 5' to 3', the polymerase is said to move along the template from 3' to 5'.

Meiosis

  • Meiosis halves the chromosomal complement of a cell.

DNA Molecule Characteristics

  • DNA is the molecule that stores genetic information.
  • DNA consists of two paired and antiparallel polynucleotide chains.
  • DNA contains four nitrogenous bases: adenine, thymine, guanine, and cytosine.
  • The nucleotides in DNA contain the sugar deoxyribose (not ribose).
  • Nucleotides are joined by phosphodiester bonds.

Polysomes

  • A polysome is a complex of ribosomes associated with the same mRNA.

Red Blood Cells

  • Red blood cells contain hemoglobin, transport oxygen, and do not directly protect the body from infections or produce antibodies.

Genetic Code Universality

  • The genetic code is universal, meaning that if a gene from a eukaryotic cell is transferred to a prokaryotic cell, it is possible that the gene encodes an identical protein in both cells.

Tricarboxylic Acid Cycle Products

  • The tricarboxylic acid cycle (Krebs cycle) produces NADH, FADH2, ATP/GTP, and carbon dioxide.

Genome Duplication Enzyme

  • DNA polymerase duplicates the genome of cells.

Blood-Brain Barrier Cells

  • Astrocytes contribute to forming the blood-brain barrier.

Ribosome Structure

  • Ribosomes contain rRNA and proteins, but not mRNA binding site.

Post-translational Modifications of Proteins

  • Post-translational modifications of proteins include glycosylation, phosphorylation, acylation, and methylation but not splicing.

Krebs Cycle

  • In the Krebs cycle, the enzyme succinyl-CoA synthetase modifies succinyl-CoA and requires GDP + Pi.

Ginglyms (Hinge Joints)

  • Ginglyms allow for angular movements.

Astigmatism

  • An astigmatic person has blurry vision due to abnormal curvature of the lens or cornea.

Meiosis and Chromosomal Combinations

  • If a diploid cell with 4 pairs of chromosomes undergoes meiosis, it can produce 16 (242^4) different chromosomal combinations due to independent assortment.

Bacterial Structures

  • Bacteria never have a nucleus.

Golgi Apparatus Function

  • The Golgi apparatus is responsible for the maturation of plasma membrane proteins and secretory proteins.

Chromatin Composition

  • Chromatin is a complex made up of DNA, acidic and basic proteins (histones), and RNA.

DNA Location in Eukaryotic Cells

  • In a eukaryotic animal cell, DNA is located in the nucleus and in the mitochondrion and also in other organelles.

Speciation

  • Speciation and the division of organisms in hierarchical levels higher than that of species is macroevolution.

DNA Length in Human Cells

  • The DNA contained in the nucleus of a human somatic cell is about 2 meters long.

Okazaki Fragments

  • Okazaki fragments are joined by DNA ligase.

Telomeres

  • Telomeres are found at the ends of eukaryotic chromosomes.
  • Telomeres shorten with each cell division.
  • Telomeres can be lengthened by the enzyme telomerase.
  • Telomeres may act as a “mitotic clock” controlling death and senescence.

Plasma Composition

  • Plasma is the liquid part of the blood.

DNA Double Helix Composition

  • If thymine content is 34% in a DNA double helix, then guanine content will be 16%.
    Rules:

  • A=TA=T and C=GC=G

  • A+T+C+G=100%A+T+C+G = 100\%

Thus:

  • A=T=34%A=T=34\%
  • C=G=(100−34−34)/2=32/2=16%C=G = (100 - 34 - 34) / 2 = 32 / 2 = 16\%

Chloroplasts vs. Mitochondria

  • Chloroplasts convert light energy into chemical energy; mitochondria perform cellular respiration and consume oxygen.
  • Both have their own DNA.

Gene Control

  • In primroses, the K gene controls malvidin synthesis (blue pigment).
  • Epistasis: The presence of at least one dominant allele in the D locus inhibits pigment production.
  • K−D−K-D-: Colorless
  • K−ddK-dd: Pigmented
  • kkD−kkD-: Colorless
  • kkddkkdd: Colorless

Cell Membrane Composition

  • Triglycerides are not components of the cell membrane of animal cells.
  • Components include proteins, phospholipids, cholesterol, and glycolipids.

Bicarbonate and Renal Function

  • Renal absorption of bicarbonates is largely dependent on hydrogen ions that are produced in the erythrocyte.

Acid-Base Balance

  • The carbon-bicarbonate system influences the activity of the other systems.
  • Hemoglobin acts as a buffer.
  • The binding of hemoglobin to oxygen decreases its affinity for hydrogen ions.

Desmosomes

  • Desmosomes are protein junctional systems.

Regulation of Renal Activity

  • Regulation of renal activity is modulated by a negative feedback mechanism by the hormone ADH and the renin-angiotensin-aldosterone system.

Sarcomere Structure

  • Sarcomeres are contractile units of myofibrils.
  • Their margins are called Z lines.
  • Sarcomere includes bands I (light), A-bands (dark), M lines, and Zone H.

Hair Cells

  • Hair cells in the utricle and saccule detect the position of the head in relation to gravity.

Hemoglobin

  • Hemoglobin is a transport chromoprotein.

Kidney Filtration

  • In the kidney filtration: It occurs thanks to the blood pressure that pushes the water and solutes through the fenestrated endothelium of the glomerular capillaries, allows the passage of proteins into Bowman's capsule, and allows water and some solutes to be recovered from the filtrate and returned to the blood.

Viral Lytic Cycle

  • In the lytic viral cycle, the viral genome does not integrate with that of the host cell.
    -The virus induces the cell to replicate it, new virions are produced and the cycle ends with the rupture of the cell membrane.

Zygote

  • The zygote is a fertilized egg cell.

Down Syndrome

  • Down syndrome is a disease due to a chromosomal abnormality.

Plasmolysis

  • A plant cell undergoes plasmolysis when it is immersed in a highly hypertonic solution.

Theories of Creation

  • Fixism is the theory that all living beings, after creation, have no changes made.

Mitochondria

  • Mitochondria are not present in prokaryotic cells.
    • Mitochondria have their own DNA.
    • Mitochondria produce ATP.
    • Mitochondria are semi-autonomous.

Melatonin

  • Melatonin is a hormone made up of a modified amino acid.
  • Melatonin regulates the circadian sleep-wake rhythm and the seasonal rhythm.
  • Melatonin is produced by melanocytes.

AB0 Blood System

  • The blood group is due to antigens present on erythrocytes.

Lactic Fermentation

  • Lactic fermentation allows NADH to be oxidized

DNA Genome

  • DNA makes up the genome of all living organisms except some viruses.