Question 1

In the human body, fibrinogen is necessary for sealing cuts and stopping the loss of blood. Since fibrinogen is made of chains of amino acids, it is an example of which type of organic molecule?

Accepted Answer

A) carbohydrate 
B) protein 
C) fatty acid 
D) nucleic acid

Question 2

A species of parasitic fly follows the sounds that male crickets make with their wings. The flies deposit their larvae in the crickets' bodies. As the larvae develop and emerge from the crickets' bodies, the crickets die.Researchers have discovered a genetic mutation in some crickets that changes their wing structure and makes them silent. The crickets with silent wings are found among crickets with normal wings when it is time to mate.According to evolution by natural selection, which of the following will most likely occur in the cricket population, based on the selection pressure from the flies?

Accepted Answer

A) Male crickets with silent wings will increase in frequency. 
B) The frequency of the silent wing mutation will stay the same. 
C) Male crickets with normal wings will learn to make new sounds. 
D) A new mutation will create spikes on the crickets' wings to keep the flies away

Question 3

Scientists have concluded that snakes evolved from an ancestor with legs. Which of the following statements provides the best evidence for this conclusion?

Accepted Answer

A) Most species of snakes live on land. 
B) Snakes move extremely fast to catch their prey. 
C) Snakes have a well-developed backbone and muscular system. 
D) Some species of snakes have limb buds during their embryonic development.

Question 4

The water cycle would not occur if which of the following were missing?

Accepted Answer

A) animals 
B) bacteria 
C) ice caps 
D) solar energy

Question 5

Which of the following provides the most conclusive evidence that organisms of two different species share a common ancestor?

Accepted Answer

A) They live in the same ecosystem. 
B) They reproduce at the same time. 
C) They have similar DNA sequences. 
D) They have similar body movements.

Question 6

Which of the following is the basic structural unit of the nervous system?

Accepted Answer

A) axon 
B) neuron 
C) red blood cell 
D) white blood cell

Question 7

High levels of carbon dioxide in the blood trigger which of the following responses in the body?

Accepted Answer

A) an increase in the rate of digestion 
B) an increase in the rate of breathing 
C) a decrease in the speed of the pulse 
D) a decrease in the production of sweat

Question 8

Which of the following would most likely happen if grasses and shrubs were removed from a rural Massachusetts ecosystem?

Accepted Answer

A) There would be an increase in consumers in the ecosystem. 
B) There would be an increase of photosynthesis in the ecosystem. 
C) There would be a decrease in food energy produced by the ecosystem. 
D) There would be a decrease of carbon dioxide available to the ecosystem.

Question 9

Which of the following statements best compares sensory neuron function and motor neuron function in the human body?

Accepted Answer

A) Sensory neurons are voluntarily controlled, whereas motor neurons are involuntarily controlled. 
B) Sensory neurons respond to light and sound stimuli, whereas motor neurons respond to touch stimuli. 
C) Sensory neurons send signals to motor neurons, whereas motor neurons send signals to the central nervous system. 
D) Sensory neurons send signals to the central nervous system, whereas motor neurons receive signals from the central nervous system.

Question 10

Unlike dairy milk, soymilk provides some of the body's daily requirement for iron. In which of the following functions of the human body does iron serve a primary role?

Accepted Answer

A) conducting nerve impulses 
B) strengthening bone structure 
C) causing muscle fibers to contract 
D) helping transport oxygen in the blood

Question 11

An endangered species is most vulnerable to extinction when it has which of the following characteristics?

Accepted Answer

A) a high birthrate 
B) a large variety in its diet 
C) a small amount of competition 
D) a small amount of genetic diversity

Question 12

All organisms have ways to produce ATP. Which of the following statements describes why ATP is a critical compound for all cells?

Accepted Answer

A) It causes mitosis to begin. 
B) It is an energy-transfer molecule. 
C) It is a major component of cell membranes. 
D) It carries information from DNA to the ribosomes.

Question 13

Which of the following best explains how the fossil record provides evidence that evolution has occurred?

Accepted Answer

A) It indicates that forms of life existed on Earth at least 3.5 billion years ago. 
B) It indicates the exact cause of structural and behavioral adaptations of organisms. 
C) It shows how the embryos of many different vertebrate species are very similar. 
D) It shows that the form and structure of groups of organisms have changed over time.

Question 14

In fish of the species Perissodus microlepis, some individuals have mouths that open to the right and some individuals have mouths that open to the left. The direction of the mouth opening is a genetic trait controlled by a single gene. The allele for a right-opening mouth (R) is dominant to the allele for a left-opening mouth (r). If two fish heterozygous for the mouth trait are crossed, what is the expected ratio of phenotypes in the offspring?

Accepted Answer

A) 1 right-opening mouth : 3 leftopening mouth 
B) 2 right-opening mouth : 2 leftopening mouth 
C) 3 right-opening mouth : 1 leftopening mouth 
D) 4 right-opening mouth : 0 leftopening mouth

Question 15

Frogs, lizards, and birds all have a similar arrangement of bones in their limbs. Which of the following does this similarity most likely indicate about these animals?

Accepted Answer

A) They move in the same way. 
B) They have a common ancestry. 
C) They evolved at the same time. 
D) They are comparable in size as adults.

Question 16

A pedigree is a diagram that traces the inheritance of a trait through a family. Which of the following patterns is typical in a pedigree for an autosomal dominant trait?

Accepted Answer

A) The trait affects only males. 
B) The trait appears in every generation. 
C) The trait appears in only one-fourth of the individuals. 
D) The trait affects all the individuals of the second generation.

Question 17

Some willow trees alter the chemical composition of their leaves when attacked by caterpillars. Compared to normal leaves,the chemically altered leaves are less nutritious and are more difficult for caterpillars to digest.Which of the following is a likely effect of this ability to alter leaf composition?

Accepted Answer

A) Willow trees with this ability will attract more caterpillars than other willow trees. 
B) Willow trees with this ability will have a survival advantage over other willow trees. 
C) More butterflies will lay their eggs on willow trees with this ability than on other willow trees. 
D) Caterpillars that feed on willow trees with this ability will be larger than caterpillars on other willow trees.

Question 18

Why is the particular sequence of bases in a segment of DNA important to cells?

Accepted Answer

A) Some base sequences code for protein production. 
B) Some base sequences cause the release of lipids from the nucleus. 
C) Some base sequences contain the order of sugars in polysaccharides. 
D) Some base sequences produce electrical signals sent to the cytoplasm.

Question 19

Which of the following best explains why enzymes are necessary for many cellular reactions?

Accepted Answer

A) Enzymes supply the oxygen necessary for the reactions. 
B) Enzymes change reactants from solid to liquid during the reactions. 
C) The reactions take up too much space in the cell if enzymes are missing. 
D) The reactions are too slow to meet the needs of the cell if enzymes are missing.

Question 20

Lobsters and spiders are both classified in the phylum Arthropoda. Lobsters and spiders are therefore also classified in the same

Accepted Answer

A) class. 
B) family. 
C) genus. 
D) kingdom.

Exam 1: Biology