Download 2.1 Sec.RevKey

Using Vocabulary
Chapter 2.1 Section Review Answer Key
1. Sunlight can be a stimulus.
2. Living things are made of cells
3. Understanding Concepts
a.
b.
c.
d.
e.
f.
All organisms, or living things are made up of one or more cells.
All organisms, or living things can sense and respond to stimuli.
All living things reproduce to make offspring either sexually or asexually.
All organisms, or living things have DNA (deoxyribonucleic acid) in their cells.
All organisms, or living things use energy to carry out life processes.
All organisms, or living things grow and develop during their life span.
4. Comparing
In asexual reproduction, there is only one parent. Since there is only one set of DNA passed
from parent to offspring, the offspring are identical to the parent. Sexual reproduction on the other
hand involves two parents. The offspring share characteristics of both parents because the offspring
will get half of its DNA from one parent, and half from the other. The offspring will be similar to the
parents but not identical to either one.
Critical Thinking
5a. The traits of parents are passed to their offspring through the DNA.
5b. If two California quails mate and reproduce their offspring could end up having
feathers, nesting habits or bird calls similar to the parents.
6. Identifying Relationships
A bear’s fur keeps the bear warm when temperatures are cold, which helps to
maintain the bear’s internal environment, or homeostasis (internal balance).
7. Math Skills
Bacteria double every generation--so after 5 generations there will be 32 bacteria.
first generation = 1 bacterium; (1x2=2)
second generation = 2 bacteria; (2x2=4)
third generation = 4 bacteria; (4x2=8)
fourth generation = 8 bacteria; (8x2=16)
fifth generation = 16 bacteria; (16x2=32)
8. Challenge
One of the advantages of sexual reproduction is that the offspring are not exactly like either one
of the parents. If a parent has an undesirable trait like a genetic disease, the offspring may not
inherit that undesirable trait. That would be an advantage.