Biology Pre-TEST 2025

A dichotomous key of different mollusks is shown.

Which mollusk moves by jet propulsion and does not have an external shell?

• A. Squid

• B. Slug

• C. Nautilus

• D. Snail

Which statement best describes how a virus replicates?

• A virus divides into two identical virus particles before infecting the host cell.

• A virus enters a host cell and uses the materials from the host cell to produce new virus particles.

• Multiple virus particles fuse and form a large particle that breaks apart, releasing new virus particles.

• Multiple virus particles break down in component parts, which then reassemble into new copies of the virus.

Biting flies can transmit diseases and cause loss of blood for animals in nature. Horses have developed behaviors to repel biting flies such as ear twitching, head tossing, leg stomping, and tail swishing.

• The nervous system senses the biting flies and sends a signal to the muscular system to move.

• The circulatory system senses the biting flies and sends a signal to the nervous system to move.

• The muscular system senses the biting flies and sends a signal to the integumentary system to move.

• The integumentary system senses the biting flies and sends a signal to the circulatory system to move.

Oil spills in the ocean affect marine food webs. Animals that are

initially affected by oil spills include sea otters, seabirds, and other

organisms that spend most of their time on the ocean surface.

Based on the food web, how would a significant decrease in the sea otter population due to an oil spill most likely affect this ecosystem?

• The sea urchin population would increase causing the kelp population to decrease.

• The fish population would increase in response to the changes in the mussel population.

• The mussel population would increase in response to the changes in the algae population.

• The killer whale population would increase causing the fish population to decrease.

Which of these shows an example of an insertion mutation?

• R S T U V ● X Y Z → S T U V ● X Y

• R S T U V ● X Y Z → R S T V ● X Y Z

• R S T U V ● X Y Z → R U T S V ● X Y Z

• R S T U V ● X Y Z → K L R S T U V ● X Y Z

In a Central Texas grassland, the producers incorporate 12,000 kJ of energy from the sun into their tissues. About how much energy would be incorporated into the tissues of herbivores?

• 12,000 kJ

• 1,200 kJ

• 10,800 kJ

• 1,080 kJ

Positive thigmotropism is a response in plants in which they move and grow toward an object the plant comes into physical contact with, usually curling around the object. This response of the shoot system benefits the plant by allowing the plant to —

• produce more pollen for pollinators

• take in more carbon dioxide to convert into glucose

• absorb more water to transport to the leaves

• reach more sunlight for photosynthesis

White clovers, Trifolium repens, are plants that are native to Europe and Central Asia and are able to produce the poison cyanide within their cells. Skunk cabbage, Symplocarpus foetidus, is a plant that is native to eastern North America and can produce a chemical that makes it have a strong, foul odor and bitter taste. The chemicals produced by both the white clovers and skunk cabbages are adaptations that allow them to —

• attract more pollinators

• survive a long-term drought

• protect against herbivores

• grow better in colder habitats

A model of the genetic control of coat color in rabbits is shown.

Which Punnett square represents a cross that would produce albino offspring?

• 
• 
• 
• 

Which factor will most directly determine what type of specialized cell will be produced?

• The size of the cell

• The length of the cell cycle

• The number of chromosomes that are replicated

• The genes that are expressed