Natalia Chapman
Anatomy and Physiology
Exam Re-grade III

1a. A – For this question I lost points because I honestly got mixed up with the words spermatogonia and spermatozoon. Spermatogonia is actually the specialized cells that sperm production beings with, these cells lie on the basement membrane of the seminiferous tubule. When the spermatogonia begin to divide sperm production begins.
B – The correct answer should be spermatozoa or spermatozoon. In the first division of sperm development, two daughter cells are produced mitotically (cell divides into two daughter cells) from the spermatogonia. One of the daughter cells migrates slightly away from the wall and develops into four sperm (each sperm consist of 23 chromosomes instead of 46), while the other one stays behind for future development of sperms. Primary then two secondary spermatocytes are also developed from these spermatogonia. Then four spermatids are developed from the secondary spermatocytes, which then mature into the four sperms. These matured sperms can now be referred to as spermatozoon, sperm, or gamete.
C – This information can be found in the Male reproductive system package on page 3(4) and page 4(c). Also some of the information was found in the textbook (same chapter) on page 1047.

2a. A- My approach to this question was correct but I missed one of the most important structures, which was the nucleus that fills most of the head and contains a haploid set of condensed, genetically inactive chromosomes.
B – The correct drawing along with the labelling and descriptions is below .

C. This information can be found in the Male reproductive system package on page 4 (1). Also in the textbook, same chapter on page 1047.

3a. A – When I approached this question I was only focusing on the function of the blood testis barrier, I absolutely didn’t think to mention why this barrier is there in the first place. Even though the blood testis barrier do prevent the blood from getting into the tubule it was not stating why.
B – So the correct answer should be the blood testis barrier functions to prevent antibodies and other large molecules that travel in the blood and also intercellular fluid from getting into the germ cells of the tubules. This is because these germ cells are different genetically from other cells in the body, so the antibodies of the immune system will attack them because they are considered foreign cells of the body. So this blood testis barrier acts as a protection to the germ cells by preventing any communication between them.
C – This answer can be found in the textbook, Chapter 27 – Male reproductive system on page 1037.
4aii. A – I lost points in this question because I was thinking the opposite for the two. My thought on the Prostaglandins was that they are responsible for the adhering of the sperm to the vagina. This is definitely incorrect because fibrinogens are produced for this function not prostaglandins.
B – The correct answer should Prostaglandins causes contractions of the uterus, because they are produced in the seminal vesicles to stimulate the vagina to contract and reduce the thickness of the vaginal secretions. Both actions help with the movement of sperms to the egg.
C – This information can be found in the Male Reproductive chapter/package on page 6 (E-1-a[2 and 3] ).

4v. A – This answer was incorrect because it was mistaken with the answer above (prostaglandins). It is incorrect because it performs a different function it does not cause the contraction in the uterus, the prostaglandins cause the contractions.
B – The fibrinogens that are also produced in the seminal vesicles actually causes the semen to adhere to the vagina wall after ejaculation. It causes the sperm to be sticky so that it can stick to the walls in the vagina. So the correct answer should be fibrinogen helps the sperm to stay in the vagina.
C – Information for this question can be found on page 6 (E) of the Male Reproductive chapter/ package.