1. studies conducted in england during the industrial revolution have shown that children born to poor families were, on average, shorter than those born to wealthier parents. the most likely explanation for this difference in height is a difference in
a nutrition.
b family size.
c genetic makeup.
d genetic disorders.

2. a woman with a genetic disease marries a man who does not carry the disease. it is not possible for their children to carry the disease. the disease must be
a sex-linked.
b recessive.
c dominant.
d caused by an extra chromosome.

3. which of the following is an example of inbreeding?
a a farmer chooses the cows in his or her herd that produce the most milk and breeds only those cows.
b a farmer chooses the cows in his or her herd that produce the most milk and breeds them with cows that get sick less often.
c a farmer chooses the cows in his or her herd that produce the most milk and injects them with hormones that make them produce more milk.
d a farmer chooses the cows in his or her herd that produce the most milk and pulls them out of the breeding stock.

4. which of the following in an advantage that a farmer would see when using a genetically engineered crop?
a introducing chemicals in the environment.
b increasing an animal's resistance to antibiotics.
c increasing the amount of crop harvested.
d reducing the resistance of a crop to pesticide.

5. which of the following correctly identifies the sequence of stages of human development?
a embryo > zygote > fetus > embryo
b blastocyst > embryo > fetus > zygote
c zygote > blastocyst > embryo > fetus
d blastocyst > zygote > embryo > fetus

6. the new cell that is formed from fertilization is called a(n)
a ovum.
b blastocyst.
c zygote.
d sperm.

7. egg-laying land animals have evolved to produce eggs with tough shells to ensure that
a external fertilization can take place.
b the egg and the sperm can fuse.
c parental care is unnecessary.
d the developing embryo does not dry out.

8. which of the following characteristics are true for both plants' and animals' reproduction?
a alternation of generation.
b they carry hereditary material from parent.
c characterized by sexual reproduction.
d the offspring looks identical to its parents.

9. a woman gives birth to a son. what is the probability that her second child will be a girl?
a 0 percent
b 25 percent
c 50 percent
d 100 percent

10. two identical flowering plants are planted in neighboring yards. one plant grows tall and healthy, producing numerous pink flowers. the other is small, has brown leaves, and never flowers. what could be the difference between the two plants?
a one of the plants is in the sporophyte generation, which does not flower, while the other is in the gametophyte generation.
b one of the plants has access to the pollinator it needs, while the other does not.
c one of the plants contains the genetic information that tells it to flower, while the other does not.
d one of the plants has the nutrients and light it needs to grow and flower, while the other does not.

11. over time, a plant pollinated by a hummingbird has developed very long, tube-like flowers. why might the flower have adapted in this way?
a the longer, tube-shaped flowers probably developed to keep the hummingbird from reaching and drinking the flower’s nectar.
b the longer, tube-shaped flowers probably developed so that the hummingbird must stick its head in the flower to drink the nectar.
c the longer, tube-shaped flowers probably developed so that pollen would not fall into them as a hummingbird flies past.
d the longer, tube-shaped flowers probably developed so that hummingbirds could land on them.

12. how do the cherries on a cherry tree the plant reproduce?
a cherries develop into seeds, which are young, undeveloped plants.
b animals eat the cherries, which disperse the plant’s seeds.
c pollen inside the cherries fertilizes ovules, which produce seeds.
d cherries are carried away by the wind, which means the seeds do not have to compete for resources.

14. the scientific name for a plant that reproduces with flowers is a(n)

15. at certain times of the year, the male sage grouse can be seen inflating the air sacs on his chest and singing loudly to a female sage grouse. this behavior is likely an example of a(n)

16. in humans, the developing embryo receives nutrients and oxygen through a tube called the