Biology 160 Chapter 1

What is the molecular commonality that is the basis of life's variety? DNA protein the ecosystem natural selection

DNA The uniformity of coding in DNA is virtually universal. Life's variety arises from variations in DNA sequences

Which of the following is true with regard to the relationship between ecosystems and communities? Ecosystems exclude the living components of an environment; communities include the living components of an environment. Soil is an ecosystem component; water is a community component. Ecosystems include the nonliving components of an environment; communities include only the living components of an environment. An ecosystem is a part of a community.

Ecosystems include the nonliving components of an environment; communities include only the living components of an environment. This is the difference between an ecosystem and a community

Local farmers think that a commonly used pesticide is responsible for the increase in appearance of frogs with an additional appendage. To test this hypothesis, frogs are injected with a small amount of pesticide mixed in ethanol. The frogs are allowed to produce offspring to test the effect of the pesticide. Which of the following would be the best controlled experiment? One group is injected with pesticide, and one group is not injected with anything. One group is injected with pesticide. One group is injected with ethanol, and one group is injected with pesticide. One group is injected with ethanol, one group is injected with pesticide, and one group is not injected with anything.

One group is injected with ethanol, one group is injected with pesticide, and one group is not injected with anything. The two control groups allow you to test a single variable, the pesticide

Which of the following statements is NOT true about discoveries that have been made as a result of comparison of DNA sequences across many species? The actions of genes in other species have been studied. Genes shared across many species have been identified. These studies have led to the identification of unknown organisms, such as some of the bacteria in your gut. Organisms possessing a genetic code drastically different from that used by humans have been discovered.

Organisms possessing a genetic code drastically different from that used by humans have been discovered. This statement is false. All organisms share the same genetic code. Thus, this statement is not true. Provide Feedback

Scientific experimentation is important in that it allows the experimenter to __________. confirm the hypotheses with certainty measure the variable being tested without error reject some alternative hypotheses obtain qualitative rather than quantitative results

Reject some alternative hypotheses. Hypotheses can be rejected when contradictory evidence emerges.

The chemical energy used by most organisms for metabolism and growth ultimately comes from __________. the sun heat carbon dioxide the decomposition of plants

The Sun

As we respire, we release CO2. The carbon in this CO2 is obtained from __________. the food we eat the air we breathe the water we drink sunlight

The food we eat. Animals eat plants, and plants fix carbon dioxide from the atmosphere into sugars through the process of photosynthesis. Humans then eat the plants (or animals that have eaten the plants), obtaining carbon, which is then metabolized to produce CO2. The CO2 is then exhaled back into the atmosphere.

Which of the following statements is true about the chemical nutrients in an ecosystem? They depend on sunlight as their source. They can be converted to energy. They flow through the ecosystem, and some nutrients are lost in the process. They cycle within the ecosystem and are constantly reused.

They cycle within the ecosystem and are constantly reused.

Radon is a radioactive gas that seeps into homes from the soil. It is thought to be a leading cause of lung cancer. A research team investigates this theory. They gather large amounts of data on basement radon concentrations and lung cancer rates and conclude that the more radon there is, the more likely lung cancer is to occur. After the study is published, other researchers criticize it by asserting that the studied neighborhoods with higher radon concentrations also have a higher percentage of old people and a higher percentage of cigarette smokers than the low-radon neighborhoods. Both advanced age and cigarette smoking increase the risk of lung cancer. This criticism, if correct, shows that the radon study suffered from __________. nonsystematic observation uncontrolled variables a lack of replication an unfalsifiable hypothesis

Uncontrolled Variables. An important feature of the scientific process is the controlled experiment in which two groups are established and treated exactly alike, except for the one variable the experiment is designed to test.

Which of these is an example of a population? liver a desert all of the red oak trees in a forest all of the grasses on a prairie

all of the red oak trees in a forest A population is a group of individuals of the same species.

Which series of terms is in the sequence of biological organization from the simplest to the most complex? cell, tissue, organ, population molecule, tissue, cell, membrane organism, ecosystem, community, population community, population, ecosystem, habitat

cell, tissue, organ, population

A property of life known as energy processing refers to the fact that living things __________. regulate their internal environments can sense stimuli from the environment obtain energy from their environment and use it to power their own activities and chemical reactions can reproduce

obtain energy from their environment and use it to power their own activities and chemical reactions All organisms must process energy in order to survive.

A single-celled eukaryotic organism that is neither a consumer nor a decomposer would most likely be classified in _____. A single-celled eukaryotic organism that is neither a consumer nor a decomposer would most likely be classified in _____. one of the kingdoms of Protista the domain Archaea the kingdom Animalia the kingdom Plantae

one of the kingdoms of Protista Protista is a diverse group of several kingdoms, but some of its members are algae, single-celled producers.