Mastering Biology Chapter 5

What concentration of radioactive glucose did the researchers find in the red blood cells of a 15-day-old guinea pig after an incubation time of 30 minutes?

85 mM

Identify the trend common to both the 15-day-old and 1-month-old guinea pigs' red blood cells.

Both experienced the most rapid uptake of glucose at the beginning of the experiment.

as the primary female sex hormone, produced in ovaries

Estradiol

Which of these is NOT a lipid?

RNA

is the most abundant male sex hormone, produced in testes

Testosterone

Which of the following hypotheses is a reasonable explanation for the data represented in the graph?

The red blood cells of older guinea pigs have fewer glucose transporter proteins than the red blood cells of younger guinea pigs.

What is the main difference between the trends for the 15-day-old and 1-month-old guinea pigs' red blood cells?

The younger guinea pig's cells took up more glucose than the older guinea pig's cells at all incubation times.

in calcium and phosphate metabolism

Vitamin D

An important function of cholesterol in a healthy organism is its role _____.

as a component of animal cell membranes

Which variable is the dependent variable--the variable that depended on the treatment and was measured by the researchers? Is the dependent variable on the x-axis or the y-axis?

concentration of radioactive glucose; on the y-axis

Which variable is the independent variable--the variable that was controlled by the researchers? Is the independent variable on the x-axis or the y-axis?

incubation time; on the x-axis

Which of these is rich in unsaturated fats?

olive oil

What do the blue dots represent?

the concentration of radioactive glucose found in a 1-month-old guinea pig's red blood cells after different incubation times

What do the red dots represent?

the concentration of radioactive glucose found in a 15-day-old guinea pig's red blood cells after different incubation times

Which of the following molecules can cross the lipid bilayer of a membrane directly, without a transport protein or other mechanism?

water, carbon dioxide, oxygen, lipids