MOLECULES TO ORGANISM 1
Which macromolecule is correctly matched with its primary function?
A. Carbohydrates — long-term information storage
B. Lipids — structural components of cell membranes and energy storage
C. Proteins — store genetic information
D. Nucleic acids — catalyze most metabolic reactions in cells
B. Lipids — structural components of cell membranes and energy storage
Eukaryotic organisms have membrane-bound organelles. Which of these organelles is considered the "control center" and stores the genetic material for the cell?
NUCLEUS
Which term best describes the type of cell division in which parent cells produce daughter cells with the same number of chromosomes as the parent cells?
Mitosis
Which scenario best illustrates natural selection?
A. A population of moths that all change color overnight because of weather
B. A population of insects where pesticide‑resistant individuals survive and reproduce
C. Individual animals learning a new behavior and passing it to offspring genetically
D. Formation of identical clones by mitosis
B. A population of insects where pesticide‑resistant individuals survive and reproduce
Which substance must be present to release energy from glucose?
a. Hydrogen
b.Oxygen
c.Lactic Acid
b.Oxygen
Which of the following is a correct distinction between prokaryotic and eukaryotic cells?
A. Prokaryotes have membrane-bound organelles; eukaryotes do not.
B. Eukaryotes have multiple linear chromosomes in a nucleus; many prokaryotes have a single circular chromosome without a nucleus.
C. Only eukaryotes use ribosomes for protein synthesis.
D. Prokaryotes perform cellular respiration; eukaryotes cannot.
B. Eukaryotes have multiple linear chromosomes in a nucleus; many prokaryotes have a single circular chromosome without a nucleus.
Placing wilted lettuce in cold water will make it crisp again. Which statement best describes what happens to restore the lettuce to its original condition?
A. Water left the lettuce cells by diffusion.
B. Water entered the cells of the lettuce by osmosis.
C. Osmosis caused salts to enter the lettuce cells.
D. Salts in the leaf caused water to leave the cells.
B-Water entered the cells of the lettuce by osmosis.
This process occurs in the nucleus and produces a molecule of mRNA
Transcription
If two populations become reproductively isolated and diverge, this process is called:
A. Genetic drift
B. Speciation
C. Homeostasis
D. Hybrid vigor
B. Speciation
During which phase of the cell cycle does DNA replication occur?
A. G1
B. S
C. G2
D. M
B. S
A point mutation substitutes a G for an A in the coding region of a gene, resulting in a codon change from GAA to GUA. Which of the following outcomes is most likely?
A. A silent mutation — same amino acid incorporated
B. A missense mutation — different amino acid incorporated
C. A nonsense mutation — translation stops early
D. A frameshift mutation — reading frame altered
B. A missense mutation — different amino acid incorporated
This organelle is the site of aerobic cellular respiration in eukaryotic cells.
Mitochondrion
Hitchhiker’s thumb (H) is dominant to no hitchhiker’s thumb (h). A woman who does not have hitchhiker’s thumb marries a man who is heterozygous for hitchhiker’s thumb. What is the probable genotypic ratio of their children? (make a punnet square)
50% Hh and 50% hh
In a study, two populations of the same species on separate islands show different allele frequencies after many generations. The best explanation is:
A. Gene flow between islands increased allele mixing
B. Independent evolution due to isolation and different selective pressures
C. Individuals on both islands are constantly interbreeding
D. Natural selection cannot act on island populations
B. Independent evolution due to isolation and different selective pressures
Which statement compares ATP yield correctly?
A. Aerobic respiration yields about 30–32 ATP per glucose; anaerobic fermentation yields about 2 ATP per glucose
B. Aerobic yields 22 ATP; anaerobic yields 30–3230–32 ATP
C. Both yield 36–3836–38 ATP per glucose
D. Aerobic yields no ATP; anaerobic yields all ATP
A. Aerobic respiration yields about 30–32 ATP per glucose; anaerobic fermentation yields about 2 ATP per glucose
Which of the following best describes the role of tRNA during translation?
A. Carries genetic information from the nucleus to the cytoplasm
B. Brings specific amino acids to the ribosome and matches them to mRNA codons
C. Forms the structure of ribosomes and catalyzes peptide bond formation
D. Copies DNA during replication
B. Brings specific amino acids to the ribosome and matches them to mRNA codons
A sugar, a phosphate group, and a nitrogen base form a nucleotide which is the building block (monomer) of which organic compound?
Nucleic Acid
Some flowers show incomplete dominance. If WW = white and RR = red, which phenotypic ratio would be expected in the offspring of two pink flowers?
1 Red: 2 Pink: 1 White
Homologous structures (e.g., forelimbs of mammals) indicate:
A. Convergent evolution only
B. Common ancestry with modification
C. That two organisms are the same species
D. That structures have identical functions in all species
B. Common ancestry with modification
Given this diagram of a four‑level food chain: Sun → Grass → Grasshopper → Frog → Snake, which change would most likely cause a long‑term decline in snake population size?
A. Increased nutrient runoff causing more grass growth
B. Introduction of a disease that reduces frog fertility
C. Slight increase in temperature that speeds grass growth
D. Short‑term decline in grasshopper numbers due to a storm
B. Introduction of a disease that reduces frog fertility
What are the three components of a DNA nucleotide and briefly state the role of each.
What is the role of base-pairing in DNA?
A. It stores energy for the cell
B. It provides a template for accurate DNA replication and encodes genetic information
C. It transports proteins across membranes
D. It digests cellular waste
B. It provides a template for accurate DNA replication and encodes genetic information
A diploid cell contains 2 pairs of homologous chromosomes Ss and Tt. Due to independent assortment what is the possible genetic make-up of the gametes produced by this organism?
A. SsTt
B. Ss, Tt
C. S, s, T, t
D. ST, St, sT, st
D. ST, St, sT, st
Which combination correctly lists mechanisms that drive evolutionary change?
A. Natural selection, genetic drift, gene flow, mutation
B. Photosynthesis, cellular respiration, mitosis, meiosis
C. Homeostasis, behaviorism, inheritance by acquired traits, fixed traits
D. Random mating only
A. Natural selection, genetic drift, gene flow, mutation
Which statement most accurately describes the difference between energy flow and matter cycling in an ecosystem?
A. Energy is recycled between organisms, while matter flows one-way and is lost as heat.
B. Energy flows one-way from producers to consumers and is eventually lost as heat; matter (nutrients) cycles between organisms and the abiotic environment
C. Both energy and matter are conserved and endlessly recycled without loss.
D. Matter flows one-way from consumers to producers, while energy cycles through decomposers only.
B. Energy flows one-way from producers to consumers and is eventually lost as heat; matter (nutrients) cycles between organisms and the abiotic environment