BLG 601 Lecture Notes - Lecture 14: Spermatocyte, Spermatogonium, Spermatid

75 views3 pages

harlequinzebra885

7 Sep 2018

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Spermatogonia are the cells that give rise to sperm cells. The spermatogonia divide by mitosis: one daughter cell remains a spermatogonium that can divide again by mitosis. The other daughter cell becomes a primary spermatocyte: the primary spermatocyte divides by meiosis to form secondary spermatocytes, the secondary spermatocytes divide by meiosis to form spermatids, the spermatids differentiate to form sperm cells. Sustentacular cells, in which the spermatogonia and developing sperm cells are embedded, maintain the blood-testis barrier. 28. 4 physiology of male reproduction: gnrh from the hypothalamus stimulates the secretion of lh and fsh from the anterior pituitary. Lh stimulates testosterone secretion from the interstitial cells. Inhibin has a negative-feedback effect on the anterior pituitary to reduce fsh secretion. Oogenesis and fertilization: oogonia give rise to oocytes, before birth, ogonia multiply by mitosis, during development of the fetus, many oogonia begin meiosis, but top in prophase i and are now called primary oocytes.

Related Questions

If the diploid chromosome number is 12, each cell has as 6 x 10 -6 grms of DNA, how many chromosomes, chromatids and DNA would you find in the following stages of cell division of a cell. (Assume cytokinesis after anaphase)

Stage of Cell Division	# of Chromosomes	# of chromatids	Amount of DNA
Prophase of mitosis
Prophase of meiosis I
Metaphase of mitosis
Anaphase of mitosis
Metaphase of meiosis I
Anaphase of meiosis I
Telophase of mitosis
Telophase of meiosis I
Metaphase of meiosis II
Telophase of meiosis II

turquoisecrow717

Which of the following is correctly matched?

		Prophase I - Nuclear envelope reforms,nucleolus reappears, spindle apparatus disappears
		Metaphase II - Homologous chromosomes align atthe equator (center) of the cell forming tetrads
		Anaphase II - Sister chromatids are pulled toopposite poles of the cell by contraction of spindle apparatusmicrotubules
		Cytokinesis - Division of the nucleus
		Telophase I - Nuclear envelope fragments,nucleolus disappears, spindle apparatus forms

ivoryspider500

-Complete the following sentences: metaphase of mitosis, prophase II of meiosis, crossing over, anaphase I of meiosis, variable, random fertilization, identical, random orientation, metaphase I of meiosis, prophase I of meiosis, metaphase II of meiosis, reduction division

Two processes that occur during meiosis produce genetically ____________ cells.

In a process called ____________ , paired homologous chromosomes align randomly at the cell equator. This occurs during this stage of cell division: ____________ .

In a process called ____________ , genetic material is exchanged between homologous chromosomes. This occurs during this stage of cell division: ____________ .

-Complete the following paragraph to describe nondisjunction and the resulting effects on chromosome number.

words: euploidy, primary nondisjunction, nomal, nondisjunction, secondary nondisjunction, homologous chromosomes, abnormal, trisomy, monosomy, sister chromatids, aneuploid

1.During meiosis I, ____________ separate and move towards opposite ends of the poles.

2.During meiosis II, ____________ separate and move towards opposite ends of the poles.

3.During meiosis I, if both members of a homologous pair go into the same daughter cell, ____________ is said to occur and no normal gametes are produced.

4.During meiosis II, if the sister chromatids fail to separate and both daughter chromosomes go into the same gamete, ____________ is said to occur. Half the gametes are aneuploid while the other half are euploid.

5.If an egg that contains 24 chromosomes instead of 23 chromosomes is fertilized by a normal sperm, ____________ is said to have occurred.

6.If an egg that contains 22 chromosomes instead of 23 chromosomes is fertilized by a normal sperm, ____________ is said to have occurred.

BLG 601 Lecture Notes - Lecture 14: Spermatocyte, Spermatogonium, Spermatid

Document Summary

Get access

Related Questions