UNTUU HULLUM
Overfishing occurs when more fish are removed from an ecosystem than can be maintained by the population,
Overfishing can lead to significant population declines in economically important species. The passage describes
additional impacts of overfishing on populations.
pressure affects
salmon fishery of
and 1970s, pink
n this fishery were
ihile allowing
nd 1974, the
inland spawning
approximately
to spawn at the
Isted that fishing
lower growth rates
According to the passage, which mechanism explains the observed changes in fish size over time?
A. Smaller fish produce fewer eggs than larger fish do, so they contribute fewer offspring to the next
generation.
B. Fish that are small enough to escape fishing nets are more likely to survive than larger fish.
C. Scientists found that Atlantic silversides exhibited changes in feeding and foraging rates after four
generations of selection,
D. The average size of pink salmon returning to spawn decreased from 6.0 pounds to approximately 4.5
pounds.

UNTUU HULLUM

Overfishing occurs when more fish are removed from an ecosystem than can be maintained by the population,

Overfishing can lead to significant population declines in economically important species. The passage describes

additional impacts of overfishing on populations.

pressure affects

salmon fishery of

and 1970s, pink

n this fishery were

ihile allowing

nd 1974, the

inland spawning

approximately

to spawn at the

Isted that fishing

lower growth rates

According to the passage, which mechanism explains the observed changes in fish size over time?

A. Smaller fish produce fewer eggs than larger fish do, so they contribute fewer offspring to the next

generation.

B. Fish that are small enough to escape fishing nets are more likely to survive than larger fish.

C. Scientists found that Atlantic silversides exhibited changes in feeding and foraging rates after four

generations of selection,

D. The average size of pink salmon returning to spawn decreased from 6.0 pounds to approximately 4.5

pounds.

i think that d. wind is the answer.   i missed the question when i answered a. currents.

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.