OAT (Optometry Admission Test) Biology Flashcards

24 sample cards from the Biology deck

Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.

1. Compare the actions of insulin and glucagon on blood glucose.

   Insulin lowers blood glucose (promotes uptake and glycogen storage); glucagon raises blood glucose (promotes glycogen breakdown and gluconeogenesis). Both from the pancreas.

2. What hormones do the anterior pituitary and the thyroid produce, and a key function?

   Anterior pituitary: TSH, ACTH, FSH, LH, GH, prolactin (controls other glands/growth). Thyroid: T3/T4 (raise metabolic rate) and calcitonin (lowers blood calcium).

3. Compare the female menstrual cycle hormones FSH, LH, estrogen, and progesterone roles.

   FSH stimulates follicle growth; LH surge triggers ovulation; estrogen builds the endometrium; progesterone (from corpus luteum) maintains it for potential pregnancy.

4. Describe the sliding filament model of muscle contraction.

   Actin filaments slide over myosin filaments; myosin heads bind actin, pull (power stroke) using ATP, and Ca2+ regulates by exposing actin binding sites via troponin/tropomyosin.

5. Differentiate innate (nonspecific) from adaptive (specific) immunity.

   Innate immunity is rapid and nonspecific (skin, phagocytes, inflammation); adaptive immunity is slower, specific, and has memory (B cells/antibodies and T cells).

6. Contrast humoral and cell-mediated immunity.

   Humoral immunity: B cells produce antibodies against extracellular pathogens. Cell-mediated immunity: cytotoxic T cells destroy infected/abnormal cells; helper T cells coordinate the response.

7. List the taxonomic hierarchy from broadest to most specific.

   Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species (mnemonic: Dear King Philip Came Over For Good Soup).

8. Name the three domains of life and a defining feature of each.

   Bacteria (prokaryotes, peptidoglycan walls), Archaea (prokaryotes, extreme environments, distinct membranes), and Eukarya (membrane-bound nucleus and organelles).

9. How is a species named under binomial nomenclature?

   By Genus + species, both italicized, with the genus capitalized and species lowercase (e.g., Homo sapiens).

10. Compare Gram-positive and Gram-negative bacteria.

    Gram-positive: thick peptidoglycan wall, stains purple. Gram-negative: thin peptidoglycan with an outer lipopolysaccharide membrane, stains pink.

11. How do bacteria achieve genetic variation without sexual reproduction?

    Through transformation (uptake of free DNA), transduction (DNA transfer via bacteriophage), and conjugation (DNA transfer via pilus between cells).

12. Why are viruses considered acellular and what are the two main replication cycles?

    Viruses lack cells/metabolism, needing a host to replicate. Lytic cycle: rapid replication and host lysis. Lysogenic cycle: viral DNA integrates and replicates with the host dormantly.

13. State Darwin's theory of evolution by natural selection.

    Heritable variation exists; individuals with traits better suited to the environment survive and reproduce more (differential reproductive success), so advantageous alleles increase over generations.

14. Differentiate the main types of natural selection: directional, stabilizing, and disruptive.

    Directional: favors one extreme. Stabilizing: favors intermediate, against extremes. Disruptive: favors both extremes against the intermediate.

15. Compare allopatric and sympatric speciation.

    Allopatric speciation occurs with geographic isolation of populations; sympatric speciation occurs without geographic separation (e.g., via polyploidy or niche differentiation).

16. Contrast convergent and divergent evolution (analogous vs homologous structures).

    Convergent evolution: unrelated species evolve similar traits (analogous structures) due to similar environments. Divergent evolution: related species diverge (homologous structures from common ancestry).

17. Define the ecological terms population, community, and ecosystem.

    Population: members of one species in an area. Community: all interacting populations in an area. Ecosystem: the community plus its abiotic (physical/chemical) environment.

18. Compare the symbiotic relationships mutualism, commensalism, and parasitism.

    Mutualism: both benefit (+/+). Commensalism: one benefits, the other unaffected (+/0). Parasitism: one benefits at the other's expense (+/-).

19. How does energy flow through trophic levels, and what is the 10% rule?

    Energy flows from producers to consumers to decomposers; only about 10% of energy transfers to the next trophic level, the rest lost mainly as heat.

20. Distinguish r-selected from K-selected species.

    r-selected: many offspring, little parental care, fast growth, unstable environments. K-selected: few offspring, much care, slower growth, near carrying capacity in stable environments.

21. What is the difference between primary and secondary ecological succession?

    Primary succession begins on bare lifeless substrate with no soil (e.g., after lava); secondary succession occurs where soil remains after a disturbance (e.g., after a fire).

22. Compare determinate and indeterminate cleavage in early development.

    Determinate cleavage: cell fate is fixed early (protostomes). Indeterminate cleavage: each early cell can form a complete organism, allowing identical twins (deuterostomes).

23. What are the three primary germ layers and the tissues each forms?

    Ectoderm (skin, nervous system), mesoderm (muscle, bone, blood, kidneys), and endoderm (gut lining, liver, lungs).

24. Define induction and differentiation in developmental biology.

    Induction: one group of cells influences the developmental fate of neighboring cells via signals. Differentiation: cells become specialized in structure and function through selective gene expression.

What this deck covers

Biology flashcards FAQ