19 terms

Chapter 8: Cell Reproduction Part 2/2

meiosis II is similar to mitosis because
in both meiosis II and mitosis, sister chromatids separate during anaphase
independent assortment
(1) the segregation between one allelic pair occurs independently from other allelic pairs (in meiosis, homologous chromosomes are sorted into daughter cells independently of one another), (2) helps explain the high amount of variation among offspring
(1) process that involves meiosis to form haploid sperm cells, (2) takes place in the seminiferous tubule of the testes of the male reproductive system
Sertoli cells
nutrient cells that nourish developing sperm cells
where are sperm cells located in the seminiferous tubule?
what is the process of spermatogenesis?
(1) spermatogonia (sing. spermatogonium; original diploid cells) under mitosis to give rise to primary spermatocytes, (2) primary spermatocytes undergo the first meiotic division to form secondary spermatocytes (haploid), (3) secondary spermatocytes undergo the second meiotic division to form spermatids, (4) spermatids undergo further development to eventually form sperm (haploid gametes of males), (5) involves two cell divisions
what are the main structures of the sperm?
(1) acrosome, (2) haploid nucleus, (3) mitochondria, (4) flagellum
sperm flagellum
whip-like structure that is able to propel the sperm so that it can reach the egg
sperm mitochondria
(1) located at the base of the flagellum, (2) provide fuel for the movement of the sperm
sperm acrosome
(1) located within the tip of the head of the sperm, (2) holds special enzymes that are able to help penetrate the egg
(1) process that involves meiosis to form a haploid egg cell and three haploid polar bodies, (2) takes place in the ovary of the female reproductive system
how is cytokinesis in oogenesis different from normal cytokinesis?
cytokinesis during oogenesis is unequal, resulting in an egg that has a lot pf cytoplasm and smaller cells called polar bodies
polar bodies
(1) small cells produced during oogenesis which contain little or no cytoplasm and eventually degenerate, (2) function to conserve cytoplasm in the developing oocyte for the egg cell
what is the process of oogenesis?
(1) the oogonium develops into a primary oocyte, (2) primary oocyte undergoes meiosis I to form one polar body and the secondary oocyte (haploid cell), (3) the secondary oocyte undergoes the second division of meiosis only when it is fertilized, and produces the ovum and another polar body, (4) the polar bodies will degenerate as the ovum develops into the ovum
primary oocyte
(1) immature ovum before the first division of meiosis I, (2) enclosed by the follicle; and as the primary oocyte develops into the secondary oocyte, the follicle grows
secondary oocyte
(1) immature ovum after the first meiotic division, but before the second meiotic division, (2) ruptures from the follicle and will remain a secondary oocyte unless it is fertilized
(1) structure in the ovary that secretes estrogens and houses the developing ovum, (2) after the secondary oocyte ruptures from the follicle, the follicle tissue becomes the corpus luteum
corpus luteum
(1) structure that forms from the developing ruptured follicle, (2) produces progesterone
In female germ cells, when does prophase I begin and end?
begins in early fetal development and ends years later