Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Micro > Gametogenesis > Flashcards

Gametogenesis Flashcards

1
Q

What is the main goal of meiosis?

A

-reduce chromosome #s (diploid -> haploid in gametes)
-crossing over & exchange of genetic material between male-female chromatids
-produce 4 daughter cells (genetically distinct)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe gametogenesis.

A

-formation of male & female gametes
-sperm & ova from spermatogonia & oogonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe mitosis.

A

-spermatogonia & oogonia (gonadal stem cells) multiply within gonad with a full set or diploid # of chromosomes (2N) specific to the species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe meiosis I & II.

A

-Spermatocytes & oocytes are produced & exchange genetic material between male & female chromatids
-divide to ensure haploid # of chromosomes (1N) in sperm & ova

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe fertilization.

A

-sperm penetrates ovum to restore diploid # of chromosomes (2N) to make zygote

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the hypothalamic-pituitary-gonadal axis.

A

negative feedback
Gonads = endocrine & gametogenic functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe primordial germ cells.

A

-primary undifferentiated stem cells that will differentiate into female & male germ cells = spermatogonia or oogonia = develop into mature male & female gametes = spermatozoa or ova through spermatogenesis or oogenesis
-PGCs appear during early embryo development
-PGCs proliferate & migrate toward genital ridge of developing gonad

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the male gonad (testis).

A

Key hormones:
-GnRH
-FSH
-LH
-testosterone
-inhibin

Key mechanism:
-LH -> leydig cells -> testosterone
-FSH -> Sertoli cells -> inhibin, ABP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe leydig cells.

A

-respond to LH to make testosterone or other androgens that help w sexual development & support to Sertoli cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe Sertoli cells.

A

-respond to FSH to make inhibin & androgen binding proteins & nourish developing sperm cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Picture of Sertoli & cells of leydig.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe spermatogenesis steps.

A
  1. spermatogenesis: begins at puberty when HPG axis matures & testosterone rises (continuous after puberty)
  2. mitosis: spermatogonia divide to make diploid primary spermatocytes
  3. Meiosis I: primary spermatocytes duplicate paternal & maternal chromosomes, homologous chromosomes crossover, exchange DNA, & divide to make haploid secondary spermatocytes
  4. Meiosis II: divide to make spermatids
  5. Maturation: transform spermatids to spermatozoa or sperm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe sperm characteristics.

A

-each sperm is genetically distinct
-X or Y chromosome
-acrosome of head = enzymes to penetrate ovum
-midpiece = mitochondria to make ATP (energy to propel sperm to site of fertilization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe sperm morphology in species.

A

shape & size of sperm head + length is species specific
-disc = ruminants
-pear = man, stallion
-hook = rodents
-spoon = guinea pig
-filiform = bird

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the spermatogenic cycle & wave.

A

12 stages
-spermatogenic cycle = time of one cycle
-spermatic wave = distance between stages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe sperm storage & exit.

A

STORAGE:
lumen of seminiferous tubules -> rete testis -> efferent ducts -> head of epididymis -> body & tail (stored here)

EJACULATION:
Vas deferens -> urethra (mixes w seminal plasma) -> glans penis (exit)

desposition in female = vagina, cervix, uterus

17
Q

Ovary of a bitch. (Picture)

A
18
Q

Preovulatory follicle (picture).

A
19
Q

Describe the female gonad (ovary) endocrine gland.

A

-follicle
-corpus luteum

20
Q

Describe folliculogenesis.

A

-cohort of follicle growth
-follicle selection

21
Q

Spermatogenesis VS oogenesis.

A
22
Q

Folliculogenesis VS oogenesis.

A
23
Q

Describe fertilization.

A

-union of 2 haploid gametes (spermatozoa & ovum) to restore the diploid state to form a zygote through process of ovum activation & start mitotic divisions = result in cell differentiation & embryo development

24
Q

Describe the steps of fertilization.

A
  1. Sperm prep = capacitation & acrosome reaction
  2. Sperm-ovum fusion & penetration of sperm
  3. Sperm & ovum pronuclei fusion
  4. Activate zygote
25
Q

Describe capacitation.

A

-maturation process in response to uterine & oviductal fluid secretion to prepare sperm for the acrosome reaction & fertilization

26
Q

Describe acrosome reaction.

A

-acrosomal digestive enzymes released to start fusion with ovum & penetrate through zona pellucida & PM of ovum

27
Q

Describe polyspermy.

A

-ovum is fertilization by more than one sperm
-too many centrosomes can be bad for survival of embryo
-block polyspermy: fast & slow

28
Q

Describe fast block.

A

-change in electric potential of PM preventing fusion of sperm
-influx of Na

29
Q

Describe slow block.

A

-cortical granules release enzymes = formation of a fertilization envelope around ovum
-release of Ca

30
Q

Pro nuclear fusion. (Picture)

A
31
Q

Pronuclei picture.

A
32
Q

Gametogeneis VS embryology.

A

Micro (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions