Biology EOC Review 2019 (Part 1)

19. The diagram shows molecules that a mitochondrion uses and produces during a cellular process.

• DNA

• RNA

• C₆H₁₂O₆

• ATP

20.) A partial Texas food web is shown. The populations of which organisms will most likely increase as a result of a disease that suddenly reduced the population of Texas horned lizards.

• Grasses and ants

• Ants and grasshoppers

• Grasshoppers and Texas cottonmouths

• Texas cottonmouths and red-shouldered hawks

21.) A biomass pyramid of an ecosystem is shown. Which statement provides the best explanation for the difference in biomass of organisms found at each trophic level.

• Organisms at higher trophic levels have less energy available to them than organisms at

  lower trophic levels.

• Organisms at higher trophic levels require smaller habitats than organisms at lower

  trophic levels.

• Organisms at lower trophic levels provide less energy than organisms at higher trophic

  levels.

• Organisms at lower trophic levels outcompete organisms at higher trophic levels.

22.) Conservation biologists studying cheetah populations have determined that the lack of genetic diversity among the cheetahs is due to genetic drift. Which statement explains the most likely consequence of having a low genetic diversity on the cheetah population?

• The chances of a mutation occurring in the cheetah population are decreased, increasing

  the cheetah survival rate.

• The gene pool remains in equilibrium and future generations of cheetah offspring are

  stronger and better adapted to their environments.

• The cheetah population becomes less likely to survive an outbreak of a disease or an

  environmental change, increasing the chance of species extinction.

• Genetic variability is maintained from older cheetah populations that have survived and

  endured environmental stressors.

23.) CRISPR-Cas9 is a genetic modification technique that edits parts of the genome of an organism. Using this technique scientists can add, remove, or modify sections of the DNA sequence. How can scientists use this technique to control gene expression?

• By activating or deactivating specific genes

• By calculating the number of genes different organisms produce

• By identifying how closely related one individual is to another

• By determining the number of chromosomes in an organism

24.) During secondary succession, which of these best describes why decomposing pioneer plants give way to larger, more complex plants species, such as hardwood trees?

• Increased amounts of sunlight are able to reach the ground while the pioneer species

  are decomposing.

• Increased soil temperatures from decomposing pioneer species help tree seeds germinate

  more quickly.

• Increased amounts of decomposing pioneer species remove nutrients that tree seedlings

  need to grow and mature.

• Increased amounts of soil from decomposing pioneer species allow plants with more

  extensive root systems to become established.

25.) The fuzzy millipede, Polyxenus fasciculatus, is found in Texas and is preyed upon by most species of ants. To protect itself against the ants, it ejects fibers from a tuft located at the tail end of its body. The tufts have hooks at the tips and barbs along their length that lock and interlink with the ant’s setae, small hairs that cover the body of the ant. When an ant attacks, the millipede flexes its back end toward the ant and wipes the tufts against it. As the ant attempts to remove the tufts, it entangles itself more, becoming immobilized. Which two systems most directly interact in the fuzzy millipede’s defense against ants?

• Muscular and integumentary

• Immune and muscular

• Integumentary and endocrine

• Endocrine and immune