Cell Biology Answers

Given your understanding of oogenesis and the hormonal control of the menstrual cycle, how does a combinatic (containing estrogen and progesterone) prevent pregnancy?

Choices are:

The pill stimulates the release of FSH and LH, initiating the formation of a new set of follicles.

The pill promotes development of the follicle and the primary oocyte within.

The pill encourages degeneration of the corpus luteum

The pill prevents follicular development by inhibiting the release of GnRH, FSH, and LH

Which of the following reproductive structures is the mother's contribution to the placenta?

myometrium
fimbriae
cervix
endometrium

Fever stimulates cells infected by viruses to produce interferon. How does interferon affect our ability to resist infection?

Choices are;

it inhibits viral infection of uninfected cells


it stimulates macrophages to phagocytize viruses

it enhances antibody production by T cells of the adaptive immune system

it resets the body's thermal set point

The low pH in the human stomach killsmost, but not all ingested bacteria, How does the human dgesive system prevent the surviving, pathogenic bacteria from causing infection?

Choices are:
Vomiting and diarrhea expose the pathogens to lymph nodes near the large intestine, esophagus, and mouth

Specialized cells in the digestive system signal white blood cells that a microbe has invaded

Ulceration of the digestive tract prevents pathogenic microbes from travelling elsewhere in the body


Non-pathogenic bacteria in the intestine kill invading bacteria and fungi

How does a B-cell receptor differ from a T-cell receptor?
Choices are!

the B-cell receptor is specific for bacteria, whereas the T-cell receptor is specific for viruses

the T-cell receptor exhibits specificity, whereas the B-cell receptor does not

the T-cell receptor requires help interacting with its specific antigen, whereas the B-cell receptor does not

the T-cell receptor is never released into the bloodstream, whereas the B-cell receptor is as an antibody

People with one sickle cell allele are not likely to get malaria. What is this an example of?

Structure of egg

Down syndrome, the most common genetic condition in the United States, is also called trisomy 21. What does this mean?

The type of RNA that encodes the gene sequence is _________

Explain how carbon dioxide enters through the stomata apparatus and diffuses into parechyma cells where it can participate in reactions of the Calvin cycle