5 Written questions
5 Matching questions
- amino acid
- stabilizing selection
- homologous trait
- reproductive isolation
The monomer of a protein. A central carbon attached to an amino group (-NH2), a carboxyl group (-COOH), and a hydrogen atom (-H). The fourth group is variable and defines the amino acid's chemical identity.
- b When selection pressures favor the average form of a trait.
- c The inability of individuals within a species to create offspring with members of any other species. The mark of a species is its reproductive isolation from all other species.
- d Green, leaflike structure that encloses and protects the unopened flower bud.
- e A trait found in different species that are morphologically and functionally similar and that comes from the same ancestral condition. A whale's fin and a human's arm are homologous structures.
5 Multiple choice questions
- A digestive organ that releases enzymes into the small intestine. Also an endocrine gland that regulates glucose levels in the blood by the release of insulin or glucagon from specialized cells called islets of Langerhans.
- Fingerlike projections in the small intestine that increase surface area and maximize the absorption of nutrients.
- An error in the sequence of nucleotides in DNA or RNA that in turn affects the production of proteins. There are two main types of mutations: substitution mutations and frameshift mutations. A substitution mutation occurs when one nucleotide is replaced by another; these mutations can range from ineffectual to drastic, depending on how the new nucleotide changes the protein coded for. Frameshift mutations occur when a nucleotide is either inserted or deleted into the code; these mutations are always drastic and often fatal, since an insertion or deletion will affect every codon in a particular genetic sequence by throwing the entire three-by-three codon frame out of whack.
- Energy in a community can be depicted as a pyramid of food or biomass. The availability of food, biomass, and energy from the trophic level of producers up through each subsequent level on the food web is approximately 10 percent of that available in the previous trophic level.
- A group of closely connected and similar cells that cooperate to generate a specific structure or specialized function within an organism.
5 True/False questions
cerebellum → A firm but flexible substance, found in regions of vertebrate skeletons, such as the ribs, that need to bend.
chemosynthesis → Process by which molecules are secreted from the cell. Exocytosis occurs when a vesicle fuses with the cell membrane and releases its contents to the outside.
vestigial structures → The organ of blood filtration in arthropods.
exoskeleton → A rigid, chitinous protective structure that surrounds the bodies of arthropods and provides support.
angiosperm → A vascular nonflowering plant (commonly known as a conifer) in which seeds are "naked"—collected in a cone and not protected by an ovary. The dispersion of their spermatozoids often relies on wind.