MasteringBiology Chapter 1

What does it mean to say that a gene is expressed?

Information in DNA is used to make a protein.
A protein is used to make DNA.
DNA contains the information needed to make a protein.
Lens cells make crystallin protein.

Information in DNA is used to make a protein.

How many different kinds of nucleotides does DNA contain?

2: wound in a double helix
4: A, C, T, G
5: A, C, T, G, U
Thousands: Each contains information for how to make a different protein.

4: A, C, T, G

Why doesn't a skin cell make crystallin protein?
Select all that apply.

Skin cells do not need crystallin for their function.
The crystallin gene is not present in skin cells.
Skin cells have the crystallin gene but do not express it.
Skin cells use different DNA for their genes.

Skin cells do not need crystallin for their function.
Skin cells have the crystallin gene but do not express it.

What is the correct order for the hierarchy of biological organization from the least to the most complex?

molecule, organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem

No amino acid molecule by itself can speed up or catalyze reactions between other molecules; however, when amino acids are joined together to make a protein with catalytic properties, the new structure (enzymatic protein) can speed up the rate of a specific chemical reaction. What does this illustrate?

emergent properties

Which of the following statements is true about chemical nutrients in an ecosystem?

They recycle within the ecosystem, being constantly reused.

Which of the following attributes is common to both prokaryotic cells and eukaryotic cells?

the use of DNA as the information storage molecule

How does DNA (deoxyribonucleic acid) encode information?

in the sequence of nucleotides.

Competition is central to the theory of natural selection. Why does competition occur?

Organisms typically produce too many offspring, and resources are limited.

Which of the following statements is not true of scientific experiments?

They must occur under carefully controlled conditions found in a laboratory.

In an experiment, investigators try to control all of the variables except one—the one that tests the hypothesis. Which of the following reasons is the primary rationale for controlling variables in an experiment?

To eliminate alternative explanations for the results of an experiment

Which of the following statements could not be supported or rejected by a scientific experiment?

The first living cell on Earth came from outer space

Which of the following statements is true of a hypothesis?

A hypothesis can be supported or rejected through experimentation.

Which of the following variables did Pasteur change in his experiment to test the hypothesis of spontaneous generation?

The shape of the flask

In Pasteur's experiment to test the hypothesis of spontaneous generation, why did he boil the broth in both flasks?

To kill any existing organisms in the broth

What results from the Zonosemata experiment support the sub-hypothesis that wing waving alone reduces predation by jumping spiders?

Zonosemata flies with housefly wings are attacked less frequently.

Suppose that Zonosemata flies whose own wings had been clipped and reattached were attacked more frequently than untreated Zonosemata flies. How would this result affect the reliability of the other experimental results?

All results for the experimental groups involving wing surgery would be invalid.

In animal populations, DDT causes \_____.

birth defects

DDT is \_____-soluble so it accumulates in \_____.

fat ... milk

Which one of the following statements is true?


-DDT does not help prevent disease from passing from agricultural animals to humans.
-Cost was a major factor in the United States government's decision to ban DDT.
-Many African governments concluded that the potential long-term health effects of DDT were not as serious as the immediate problem of insect control.
-DDT cannot accumulate in the fat of animals.
-The DDT ban in the United States has made it very difficult to control agricultural insect pests.

Many African governments concluded that the potential long-term health effects of DDT were not as serious as the immediate problem of insect control.

Which of these examples illustrates deductive reasoning?

You learned in elementary school that as temperature drops, liquids change into solid form. You are given an unfamiliar liquid and hypothesize that it will become solid if you put it in the freezer.

Select the correct statement about the process of scientific inquiry.

It is possible to test hypotheses, such as those involving historical events, without conducting experiments.