Biology Midterm Review

Why is the mouse population changing over time?

• The light mice can reproduce more successfully than the dark mice
• The hawks eat more dark mice than light mice because the dark mice taste better
• The hawks eat more light mice than dark mice because they can see the light mice more easily
• The hawks eat more dark mice than light mice because they can see the dark mice more easily

Which do BOTH prokaryotes and eukaryotes contain?

• nucleus

• mitochondria

• ribosomes

• cell wall

What causes differentiation?

• The DNA is different in each type of cell.

• Some cells have more or less DNA than others.

• Only specific genes in the DNA are activated.

A purple-flowered plant (PP) is crossed with a white flowered plant (WW). The gene for petal color in these plants expresses incomplete dominance. What percentage of the offspring will have blue (PW) flowers?

• 0%

• 25%

• 50%

• 100%

What is polygenic inheritance?

• Inheritance controlled by a single gene

• Inheritance controlled by multiple genes

• Inheritance that follows Mendel's rules

• Inheritance that does not involve alleles

What amino acid is represented by the codon UUA?

• Phenylalanine
• Tyrosine
• Leucine
• Stop codon

Homeostasis

• allows for a wildly fluctuating internal environment
• is impossible in vertebrates
• is the maintenance of a relatively stable internal environment

• is the maintenance of a relatively stable external environment

How do you "win" at natural selection?

• survive

• go extinct

• survive & reproduce

When glucose levels in the blood rise, your brain sends a signal to your pancreas. The pancreas releases insulin, which opens channels in cell membranes to allow glucose to enter the cell, lowering blood sugar levels. 

• Positive Feedback Response
• Negative Feedback Loop 

When one allele is not dominant over another, resulting in a blended phenotype for heterozygous offspring is considered....

• Incomplete Dominance

• Codominance