Question

part a write the letter of the correct answer in the blank.
__ 1. a population of a species is able to evolve because __.
a its environment changes c it changes slowly
b mutations occur in its gametes d all its organisms are the same
__ 2. the geologic time scale is useful to __.
a see when different kinds of organisms first appeared
b tell how various ancient organisms lived and died
c determine the relative ages of fossils
d explain why mass extinctions have occurred
____ 3. which theory explains that organisms change because of adaptations that help them survive?
a homologous structures c natural selection
b descent with modification d geographic isolation
__ 4. the group made up of humans and their humanlike ancestors is called __.
a homo sapiens c primates
b australopithecus d hominids
____ 5. which of the following would not help explain how evolution occurs?
a organisms produce many more offspring than can survive.
b all the individuals in a population are identical.
c individuals with traits best suited to the environment tend to survive.
d survivors pass on their genes (and traits) to offspring.
part b match the terms with their descriptions. write the letter of the correct answer on the line.
column a column b
____ 6. hominid a the group of mammals that includes humans
and apes
____ 7. primate b latin name meaning “handy man”
____ 8. radioactive mineral c body part that is not useful to organism but
was useful to its ancestors
____ 9. homo habilis d the group that includes humans and
humanlike relatives
____10. vestigial structure e way to date fossils

Explanation:

1. For question 1:

• Evolution occurs due to genetic changes. Mutations in gametes (reproductive cells) can introduce new genetic variations. If all organisms were the same (D), there would be no variation for evolution. A change in the environment (A) can act on variations, but the source of variation is key. Slow - changing (C) is not the cause of evolution.

1. For question 2:

• The geologic time scale shows the chronological order of different organisms' first appearances. It doesn't directly tell how organisms lived and died (B), determine relative ages of fossils (C) is more about stratigraphy in some cases, and it doesn't explain mass extinctions (D) as its main function.

1. For question 3:

• Natural selection is the theory where organisms with adaptations that help them survive are more likely to pass on their genes. Homologous structures (A) are about similar body parts, descent with modification (B) is a general concept related to evolution but not the specific theory about adaptations for survival, and geographic isolation (D) is about separation of populations.

1. For question 4:

• Hominids are the group that includes humans and human - like ancestors. Homo sapiens (A) is the species of modern humans, primates (C) is a larger group that includes humans and apes, and Australopithecus (B) is a genus within hominids.

1. For question 5:

• If all individuals in a population are identical (B), there is no variation for evolution by natural selection. Organisms producing more offspring than can survive (A), survival of the fittest (C), and passing on genes (D) are all part of the process of evolution.

1. For question 6:

• Hominid is the group that includes humans and human - like relatives (D).

1. For question 7:

• Primate is the group of mammals that includes humans and apes (A).

1. For question 8:

• Radioactive minerals are used as a way to date fossils (E).

1. For question 9:

• Homo habilis has a Latin name meaning “handy man” (B).

1. For question 10:

• Vestigial structure is a body part that is not useful to an organism but was useful to its ancestors (C).

Answer:

1. B
2. A
3. C
4. D
5. B
6. D
7. A
8. E
9. B
10. C