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🇺🇸 DAT (Dental Admission Test) · flashcards
DAT (Dental Admission Test) Biology Flashcards
55 question-and-answer cards covering Biology as it is examined in DAT (Dental Admission Test). 24 of them are printed below, taken from across the deck — no signup, no paywall on the preview.
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.
For a monohybrid cross between two heterozygotes (Aa x Aa), what is the genotypic and phenotypic ratio?
Genotypic ratio 1 AA : 2 Aa : 1 aa; phenotypic ratio 3 dominant : 1 recessive.
Define incomplete dominance and codominance with an example each.
Incomplete dominance: heterozygote shows a blended intermediate phenotype (red x white snapdragons to pink); codominance: both alleles fully expressed (AB blood type).
How is the genotype of a person with type AB blood related to allele dominance?
They have genotype I^A I^B; both alleles are codominant, so both A and B antigens are expressed on red blood cells.
Why are X-linked recessive traits more common in males?
Males are hemizygous (XY) and need only one recessive allele on their single X to express the trait, while females (XX) need two copies.
What chromosomal nondisjunction event causes Down syndrome?
Trisomy 21, caused by failure of chromosome 21 to separate during meiosis, resulting in three copies.
State the Hardy-Weinberg allele and genotype frequency equations.
p + q = 1 and p^2 + 2pq + q^2 = 1, where p^2 = homozygous dominant, 2pq = heterozygous, q^2 = homozygous recessive frequencies.
List the five conditions required for Hardy-Weinberg equilibrium.
No mutation, no natural selection, no gene flow (migration), random mating, and a very large population (no genetic drift).
In a pedigree, what pattern suggests an autosomal recessive trait?
The trait can skip generations, affects males and females equally, and unaffected (carrier) parents can produce affected offspring.
What are the four phases of the cell cycle, and what occurs during S phase?
G1, S, G2 (interphase), and M (mitosis); during S phase DNA is replicated, doubling the chromosomal DNA.
List the four phases of mitosis in order and one key event of each.
Prophase (chromosomes condense), metaphase (chromosomes align at the metaphase plate), anaphase (sister chromatids separate to poles), telophase (nuclear envelopes reform).
How does meiosis differ from mitosis in chromosome number and number of divisions?
Mitosis is one division producing two identical diploid cells; meiosis is two divisions producing four genetically distinct haploid cells (gametes).
What two events in meiosis I increase genetic variation?
Crossing over (recombination during prophase I) and independent assortment of homologous chromosomes during metaphase I.
Compare spermatogenesis and oogenesis in terms of gamete yield.
Spermatogenesis yields four functional sperm per primary spermatocyte; oogenesis yields one functional egg plus polar bodies per primary oocyte.
Name the three primary germ layers and one tissue derived from each.
Ectoderm (skin/nervous system), mesoderm (muscle/bone/blood), endoderm (gut lining/lungs).
What is the resting membrane potential of a neuron and what maintains it?
About -70 mV, maintained by the Na+/K+ pump and the membrane's higher permeability to K+ (leak channels).
How does the endocrine system differ from the nervous system in signaling?
The endocrine system uses hormones carried in the blood for slow, widespread, long-lasting effects; the nervous system uses electrical impulses and neurotransmitters for rapid, localized, short-lived effects.
Trace the path of blood through the heart starting from the body.
Body to vena cava to right atrium to right ventricle to pulmonary artery to lungs to pulmonary vein to left atrium to left ventricle to aorta to body.
Distinguish innate from adaptive immunity.
Innate immunity is nonspecific and immediate (barriers, phagocytes, inflammation); adaptive immunity is specific, slower, and has memory (B and T lymphocytes, antibodies).
What is the sliding filament theory of muscle contraction?
Myosin heads bind actin and pull the thin filaments toward the sarcomere center, shortening the sarcomere; this requires ATP and Ca2+ released from the sarcoplasmic reticulum.
Name four mechanisms of evolution that change allele frequencies.
Natural selection, genetic drift, gene flow (migration), and mutation.
List three categories of evidence supporting evolution.
Examples: fossil record, comparative anatomy (homologous/vestigial structures), molecular/DNA homology, and embryological similarities.
State the Linnaean taxonomic hierarchy from broadest to most specific.
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.
Differentiate exponential from logistic population growth.
Exponential growth (J-curve) is unlimited with constant per-capita rate; logistic growth (S-curve) levels off at the carrying capacity (K) as resources become limiting.
Why does only about 10% of energy transfer between trophic levels in an ecosystem?
The remaining ~90% is lost as heat through metabolism (respiration), used for life processes, or not consumed/digested, per the 10% rule of energy flow.
What this deck covers
The Biology deck follows the DAT (Dental Admission Test) Biology syllabus — 6 chapters and 32 topics — so questions land on material that is genuinely examinable rather than trivia around it. That works out to roughly 9.2 cards per chapter.
Answers are written to be recallable, not just readable — averaging about 131 characters, which is long enough to carry the reasoning and short enough to say out loud.
A deck like this earns its keep on the second and third pass. Read the syllabus first so you know the shape of the subject, then use the cards to find the specific facts that have not stuck.
Biology flashcards FAQ
How many Biology flashcards are in this DAT (Dental Admission Test) deck?
55 cards. This page previews 24 of them, sampled evenly across the deck so you can judge the difficulty before installing anything.
Are these DAT (Dental Admission Test) flashcards free?
Yes. The preview here is free to read with no signup, and the full 55-card deck is free inside the Examius app.
What do the Biology cards cover?
They follow the DAT (Dental Admission Test) Biology syllabus — 6 chapters and 32 topics — so the questions track what is actually examinable.
How should I use these flashcards?
Read the syllabus first so you know the shape of the subject, then drill the deck. Examius schedules each card with spaced repetition, so cards you keep missing come back sooner and ones you know drift further apart.