Comprehensive Biology Review Flashcards

Flashcards testing core concepts across all sections of the biology lecture notes, formatted strictly according to JSON schema and LaTeX requirements.

What is the difference between atomic number and mass number?

Atomic number equals the number of electrons or protons in an atom, whereas mass number equals the total number of protons plus neutrons.

What are isotopes?

Isotopes are atoms of the same element that have different numbers of neutrons but identical numbers of protons and electrons.

What is specific heat?

Specific heat is the amount of heat energy required to raise the temperature of $1\,g$ of a substance by $1\,^{\circ}\text{C}$.

At what temperature does liquid water reach its maximum density?

Water reaches its maximum density at $4\,^{\circ}\text{C}$.

How much energy is released when $1\,g$ of carbohydrate versus $1\,g$ of lipid is burned?

Burning $1\,g$ of carbohydrate releases $4\,\text{calories}$ of heat, whereas burning $1\,g$ of lipid releases $9\,\text{calories}$ of heat.

How do saturated fats and unsaturated fats differ chemically and physically?

Saturated fats contain no double bonds in their hydrocarbon chain and are solid at room temperature; unsaturated fats contain at least one double bond and are liquid at room temperature.

What cellular change occurs during plasmolysis?

Plasmolysis occurs when a cell is placed in a hypertonic solution, causing water to leave the cell and the cell to shrink.

What microtubule arrangement is characteristic of eukaryotic cilia and flagella?

Cilia and flagella both consist of $9$ pairs of microtubules organized around $2$ singlet microtubules.

How do prokaryotic and eukaryotic cells differ regarding nucleus and organelle structure?

Prokaryotic cells lack a nucleus and membrane-bounded organelles and have circular chromosomes; eukaryotic cells have a true nucleus, membrane-bounded organelles, and linear chromosomes.

How do the daughter cells of mitosis compare to those of meiosis regarding chromosome count and DNA mass relative to the parent cell?

Mitosis produces $2$ daughter cells with the same number of chromosomes as the parent cell and half the DNA mass; meiosis produces $4$ haploid daughter cells with half the number of chromosomes and one-quarter the DNA mass.

What is Mendel's Law of Segregation?

It states that during gamete formation, the two traits or alleles carried by each parent separate.

What phenotypic ratio results from a dihybrid cross between two individuals heterozygous for both traits ($YyRr \times YyRr$)?

A phenotypic ratio of $9:3:3:1$.

What is the function of helicase in DNA replication?

Helicase unzips the two strands of the original DNA helix by breaking the hydrogen bonds between paired nitrogenous bases.

What occurs during the RNA processing phase of gene expression?

Enzymes (snRNPs) remove non-coding regions called introns from mRNA and reattach the coding regions called exons.

What is a nonsense mutation?

A point mutation in DNA that results in a stop codon, causing translation to terminate early and producing a shortened or nonfunctional protein.

What is the net yield of ATP produced per glucose molecule during aerobic cellular respiration?

A total net yield of $30-32\,\text{ATP}$ ($2\,\text{ATP}$ from glycolysis, $2\,\text{ATP}$ from the Krebs cycle, and the remaining ATP from the electron transport chain).

What is photorespiration in plants?

A process occurring under hot, dry conditions where Rubisco binds to $\text{O}_2$ instead of $\text{CO}_2$, leading to the loss of already-fixed carbon.

What role do nitrogen-fixing bacteria play in the nitrogen cycle?

They live in root nodules of legumes and convert free atmospheric nitrogen ($\text{N}_2$) into ammonium ions ($\text{NH}_4^+$).

What three domains are recognized in modern biological classification?

Domain Bacteria, Domain Archea, and Domain Eukarya.

How do retroviruses convert their genetic material inside a host cell?

Retroviruses use the enzyme reverse transcriptase to translate their viral genetic information from RNA into DNA, which then integrates into the host cell's genome.

What is double fertilization in angiosperms?

One sperm nucleus fertilizes the egg cell to form the diploid embryo ($2n$), while the other sperm nucleus fertilizes the two polar bodies to form the triploid endosperm ($3n$).

What are the Hardy-Weinberg equations used for calculating allele and genotype frequencies?

$p + q = 1$ for allele frequencies and $p^2 + 2pq + q^2 = 1$ for genotype frequencies, where $p$ represents the dominant allele frequency and $q$ represents the recessive allele frequency.

What is the 10% rule of energy transfer in ecological food chains?

Only $10\%$ of stored energy at any trophic level is converted into organic matter for the next trophic level, while $90\%$ is lost as heat, metabolism, or waste.

What role does antidiuretic hormone (ADH) play in the human excretory system?

ADH is released by the posterior pituitary to increase water reabsorption in the collecting tubules of nephrons, regulating blood pressure and preventing dehydration.

What ion flows create an action potential along an axon membrane?

Depolarization occurs when sodium channels open and $\text{Na}^+$ floods into the cell, followed by repolarization when potassium channels open and $\text{K}^+$ floods out.

Which primary germ layer formed during gastrulation gives rise to the nervous system and skin?

The ectoderm.

What defines a Fixed Action Pattern (FAP) in animal behavior?

An innate, highly stereotypical behavior initiated by an external stimulus (releaser) that is carried out to completion regardless of immediate usefulness.

How do independent and dependent variables differ in a scientific experiment?

The independent variable is intentionally changed or manipulated by the experimenter, whereas the dependent variable is measured to observe the response to that manipulation.