Brainscape's Knowledge GenomeTM

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


See full index

OB1 > LE2 Gameto > Flashcards

LE2 Gameto Flashcards

1
Q

What is oogenesis?
A) The production of sperm cells
B) The development of the ovum from an oogonium by meiosis
C) The fertilization of an ovum by a sperm
D) The division of a fertilized ovum

A

B) The development of the ovum from an oogonium by meiosis

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

What is spermatogenesis?
A) The development of mature sperm from spermatogonia by mitosis
B) The growth of oogonia into mature ova
C) The development of mature sperm from spermatogonia by meiosis
D) The process of fertilization between sperm and ovum

A

C) The development of mature sperm from spermatogonia by meiosis

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

What occurs during fertilization?
A) A spermatozoon merges with an oocyte
B) An oocyte develops into a zygote
C) A morula forms from a zygote
D) A blastocyst develops from a morula

A

A) A spermatozoon merges with an oocyte

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

What is a zygote?
A) A mature sperm cell
B) The stage before the ovum is fertilized
C) The one cell stage of the fertilized ovum before the first cleavage
D) A ball of cells in the early embryo stage

A

C) The one cell stage of the fertilized ovum before the first cleavage

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

What is a morula?
A) An early stage embryo that develops into the placenta and membranes
B) A fluid-filled cavity in the embryo
C) The final stage of embryonic development
D) The initial stage of oogenesis

A

A) An early stage embryo that develops into the placenta and membranes

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

Which of the following best describes a blastocyst?
A) A structure with a fluid-filled cavity and trophoblasts, following the morula stage
B) The initial sperm cell
C) The stage of a single fertilized cell
D) An advanced embryo with developed organs

A

A) A structure with a fluid-filled cavity and trophoblasts, following the morula stage

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

What does the term ‘conceptus’ refer to?
A) Only the embryo in its earliest stages
B) The fertilized oocyte and all its derivatives until birth
C) The placenta and its membranes
D) The process of embryonic cell division

A

B) The fertilized oocyte and all its derivatives until birth

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

During which stage is the term ‘embryo’ used?
A) From fertilization until the first cell division
B) After the development of the primitive streak until major organs are developed
C) From the blastocyst stage until birth
D) Immediately after fertilization

A

B) After the development of the primitive streak until major organs are developed

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

What is conceptional age?
A) The age from the embryo’s implantation in the uterus
B) The age from fertilization
C) The age from the onset of the last menstrual period
D) The age of the embryo from the morula stage

A

B) The age from fertilization

Conceptional Age: The age of the conceptus from fertilization. This is about 2 weeks after gestational age because it’s counting from the first day of the last menstrual period (LMP).

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

What does gestational age measure?
A) The age of the conceptus from conception
B) The age from the last menstrual period to the current date
C) The development stage from the embryo to the fetus
D) The time from implantation to birth

A

B) The age from the last menstrual period to the current date

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

What happens during the G1 phase of the cell cycle?
A) DNA replication
B) Cell division
C) Cells increase in size, replicate organelles, and prepare molecular building blocks
D) Cells check for errors in DNA replication

A

C) Cells increase in size, replicate organelles, and prepare molecular building blocks

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

What is the primary activity during the S phase of the cell cycle?
A) Cell growth
B) Organelle replication
C) DNA replication and centrosome duplication
D) Cell division

A

C) DNA replication and centrosome duplication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What characterizes the G2 phase of the cell cycle?
A) Cells decrease in size
B) Rapid cell division
C) Continued cell growth and preparation for mitosis, including DNA error checking
D) Protein synthesis

A

C) Continued cell growth and preparation for mitosis, including DNA error checking

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

What occurs during the M phase of the cell cycle?
A) DNA replication
B) Cell growth and organelle replication
C) The cell divides into two daughter cells through mitosis and cytokinesis
D) Centrosome duplication

A

C) The cell divides into two daughter cells through mitosis and cytokinesis

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

Which phase is generally the longest in the cell cycle?
A) G1 Phase
B) S Phase
C) G2 Phase
D) M Phase

A

A) G1 Phase

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

During which phase is the centrosome duplicated?
A) G1 Phase
B) S Phase
C) G2 Phase
D) M Phase

A

B) S Phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the primary goal of mitosis?
A) To reduce the chromosome number by half
B) To produce two genetically identical daughter cells
C) To introduce genetic diversity
D) To produce four haploid cells

A

B) To produce two genetically identical daughter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In which cells does mitosis occur?
A) Only in reproductive cells
B) In somatic cells
C) In germ cells
D) In haploid cells only

A

B) In somatic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How many cell divisions are involved in mitosis?
A) One
B) Two
C) Four
D) None, as it is a continuous process

A

A) One

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the main purposes of mitosis?
A) Genetic diversity and sexual reproduction
B) Growth, tissue repair, and asexual reproduction
C) Reduction of chromosome number
D) Production of gametes

A

B) Growth, tissue repair, and asexual reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What distinguishes meiosis from mitosis?
A) Meiosis produces genetically identical cells
B) Meiosis results in haploid cells from a diploid parent
C) There is no cell division in meiosis
D) Meiosis occurs in all body cells

A

B) Meiosis results in haploid cells from a diploid parent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is unique about the cells produced by meiosis?
A) They are genetically identical to the parent cell
B) They are diploid like the parent cell
C) They are genetically unique due to crossing over and independent assortment
D) They do not contain chromosomes

A

C) They are genetically unique due to crossing over and independent assortment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

In which cells does meiosis occur?
A) Somatic cells
B) Germ cells
C) All body cells
D) Only in haploid cells

A

B) Germ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How many rounds of cell division does meiosis involve?
A) One
B) Two
C) Three
D) Four

A

B) Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the final product of meiosis from one diploid cell?
A) Two diploid cells
B) Two haploid cells
C) Four diploid cells
D) Four haploid cells

A

D) Four haploid cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why is meiosis important for genetic diversity?
A) It produces genetically identical cells
B) It increases the number of somatic cells
C) It involves crossing over and independent assortment
D) It only occurs in somatic cells

A

C) It involves crossing over and independent assortment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

During which phase does DNA synthesis occur in both mitosis and meiosis?
A) Prophase
B) Metaphase
C) Anaphase
D) S phase of interphase

A

D) S phase of interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is synapsis of homologous chromosomes and during which process does it occur?
A) The replication of DNA, occurring during mitosis
B) The pairing up of homologous chromosomes, occurring during meiosis
C) The division of the nucleus, occurring during mitosis
D) The alignment of chromosomes, occurring during both mitosis and meiosis

A

B) The pairing up of homologous chromosomes, occurring during meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

When does crossover occur and what is its significance?
A) During metaphase in mitosis, leading to chromosome alignment
B) During prophase I of meiosis, contributing to genetic variation
C) During anaphase in both mitosis and meiosis, leading to cell division
D) During telophase, resulting in the formation of new cells

A

B) During prophase I of meiosis, contributing to genetic variation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How do chromosomes align at the metaphase plate in mitosis compared to meiosis?
A) In both mitosis and meiosis, homologous chromosomes line up at the metaphase plate
B) In mitosis, sister chromatids line up; in meiosis I, homologous chromosomes line up, and in meiosis II, sister chromatids line up
C) In both mitosis and meiosis, sister chromatids line up at the metaphase plate
D) Chromosome alignment does not occur in either mitosis or meiosis

A

B) In mitosis, sister chromatids line up; in meiosis I, homologous chromosomes line up, and in meiosis II, sister chromatids line up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the outcome of mitosis in terms of the cells produced?
A) Two haploid daughter cells that are genetically unique
B) Four haploid daughter cells that are genetically identical
C) Two diploid daughter cells that are genetically identical to the parent cell
D) Four diploid daughter cells that are genetically unique

A

C) Two diploid daughter cells that are genetically identical to the parent cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the outcome of meiosis and how does it contribute to genetic diversity?
A) Four diploid cells that are genetically identical, increasing cell number without changing genetics
B) Two haploid cells that are genetically unique, leading to genetic variation
C) Four haploid cells that are genetically unique, contributing to genetic diversity
D) Two diploid cells that are genetically identical, maintaining the genetic status quo

A

C) Four haploid cells that are genetically unique, contributing to genetic diversity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How does meiosis differ fundamentally from mitosis?
A) It involves only one cell division
B) It results in cells that are genetically identical to the parent cell
C) It involves two main divisions and leads to the formation of haploid cells
D) It starts and completes in the embryonic stage

A

C) It involves two main divisions and leads to the formation of haploid cells

Involves two main divisions: separation of homologous chromosomes and separation of sister chromatids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

When does meiosis typically begin in humans?
A) At birth
B) At puberty
C) In early childhood
D) In adulthood

A

B) At puberty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

During prophase I of meiosis I, what is formed when homologous chromosomes pair up?
A) Sister chromatids
B) Bivalents or tetrads
C) Diploid cells
D) Spindle fibers

A

B) Bivalents or tetrads

Divided into five sub-phases.
Chromosomes condense and homologous chromosomes pair up, forming bivalents or tetrads.
Crossing over occurs, leading to the formation of recombinant chromosomes and genetic variation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the significance of crossing over during prophase I of meiosis?
A) It decreases genetic variation
B) It results in the duplication of chromosomes
C) It leads to the formation of recombinant chromosomes and increases genetic variation
D) It aligns the chromosomes at the metaphase plate

A

C) It leads to the formation of recombinant chromosomes and increases genetic variation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How are homologous chromosomes aligned during metaphase I of meiosis?
A) In a single row along the metaphase plate
B) In a double row along the metaphase plate
C) They do not align but separate immediately
D) In a circular pattern around the centromere

A

B) In a double row along the metaphase plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What occurs during anaphase I of meiosis?
A) Sister chromatids separate and move to opposite poles
B) Homologous chromosomes separate and move to opposite poles
C) Chromosomes duplicate
D) The nuclear membrane reforms

A

B) Homologous chromosomes separate and move to opposite poles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What happens during telophase I of meiosis?
A) Chromosomes decondense and a nuclear membrane forms around each set
B) Homologous chromosomes align at the metaphase plate
C) The cell divides into four haploid cells
D) DNA replication occurs

A

A) Chromosomes decondense and a nuclear membrane forms around each set

Chromosomes reach the opposite poles and a nuclear membrane may form around each set.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the result of cytokinesis in meiosis I?
A) The formation of two haploid cells
B) The formation of two diploid cells
C) The formation of four haploid cells
D) The cell returns to the interphase stage

A

B) The formation of two diploid cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the primary function of Meiosis II?
A) To duplicate chromosomes
B) To separate homologous chromosomes
C) To separate sister chromatids of each chromosome
D) To exchange genetic material between chromosomes

A

C) To separate sister chromatids of each chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

At which stage of meiosis does crossing over, where genetic material is exchanged between chromosomes, occur?
A) Prophase I of Meiosis I
B) Metaphase I of Meiosis I
C) Prophase II of Meiosis II
D) Metaphase II of Meiosis II

A

A) Prophase I of Meiosis I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How do maternal and paternal chromosomes align during Metaphase I of Meiosis I?
A) They align randomly along the metaphase plate
B) They pair up and separate into daughter cells
C) They remain attached at their centromeres
D) They align in identical positions as in the parent cell

A

A) They align randomly along the metaphase plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is the significance of the random alignment of sister chromatids during Metaphase II of Meiosis II?
A) It reduces genetic diversity
B) It increases the number of chromosomes in each cell
C) It ensures exact replication of the parent cell’s genetic material
D) It contributes to genetic diversity in the resulting gametes

A

D) It contributes to genetic diversity in the resulting gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What is the initial ploidy of the cell that undergoes meiosis, and what is the ploidy of the resulting cells?
A) Starts as diploid, results in diploid cells
B) Starts as diploid, results in haploid cells
C) Starts as haploid, results in diploid cells
D) Starts as haploid, results in haploid cells

A

B) Starts as diploid, results in haploid cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is the outcome of meiosis in terms of cell development?
A) It produces four diploid cells that replicate the parent cell’s genetic structure
B) It results in two haploid cells that are genetically identical
C) It generates four haploid cells each with a unique set of chromosomes
D) It creates two diploid cells with mixed genetic material from both parents

A

C) It generates four haploid cells each with a unique set of chromosomes

Outcome of Meiosis:

The number refers to the ploidy of the cells. The process begins with a diploid cell, which contains two sets of chromosomes (one from each parent).
After two rounds of division in meiosis, it produces four haploid cells, each with a single set of chromosomes. These cells can develop into gametes (sperm or eggs in animals). The genetic composition of the daughter cells is unique due to the mechanisms that generate diversity during meiosis I and II.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

How does the process of meiosis contribute to the genetic diversity of gametes?
A) Through the duplication of chromosomes and reduction of cell number
B) By maintaining the same genetic information as the parent cell
C) Through crossing over in Prophase I and random alignment of chromosomes in Metaphase I and II
D) By producing a large number of identical cells

A

C) Through crossing over in Prophase I and random alignment of chromosomes in Metaphase I and II

Outcome of Meiosis:

The number refers to the ploidy of the cells. The process begins with a diploid cell, which contains two sets of chromosomes (one from each parent).
After two rounds of division in meiosis, it produces four haploid cells, each with a single set of chromosomes. These cells can develop into gametes (sperm or eggs in animals). The genetic composition of the daughter cells is unique due to the mechanisms that generate diversity during meiosis I and II.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the primary function of gametogenesis?
A) To increase the number of body cells
B) To produce gametes (sperm and eggs)
C) To duplicate genetic material
D) To create somatic cells

A

B) To produce gametes (sperm and eggs)

Oogenesis and spermatogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Why is meiosis important in the formation of gametes?
A) It doubles the number of chromosomes in each cell
B) It allows for the exchange of genetic material and reduces chromosome number by half
C) It ensures each gamete has a complete set of chromosomes
D) It creates identical genetic copies of each cell

A

B) It allows for the exchange of genetic material and reduces chromosome number by half

Meiosis allows for the exchange of genetic material between homologous chromosomes, contributing to genetic diversity.

The process reduces the chromosome number by half, from diploid (46 chromosomes) to haploid (23 chromosomes).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What happens to the chromosome number during gametogenesis?
A) It remains the same
B) It increases
C) It reduces from diploid to haploid
D) It changes randomly

A

C) It reduces from diploid to haploid

The process reduces the chromosome number by half, from diploid (46 chromosomes) to haploid (23 chromosomes).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

How many chromosomes does each gamete contain after gametogenesis?
A) 46 chromosomes
B) 23 chromosomes
C) 92 chromosomes
D) 12 chromosomes

A

B) 23 chromosomes

52
Q

Why is the reduction of chromosomes to haploid necessary in gametes?
A) To allow for cellular growth
B) To ensure genetic stability in the offspring
C) So that fertilization can restore the diploid number of chromosomes in the offspring
D) To increase genetic diversity without fertilization

A

C) So that fertilization can restore the diploid number of chromosomes in the offspring

This reduction is essential so that when fertilization occurs, the complement of chromosomes from each parent (23 from the mother and 23 from the father) can combine to form a diploid organism with 46 chromosomes.

53
Q

What is the final product of meiosis in gametogenesis?
A) Two diploid cells
B) Four diploid cells
C) Four haploid gametes
D) Two haploid gametes

A

C) Four haploid gametes

54
Q

Where does spermatogenesis occur?
A) In the ovaries
B) Within the seminiferous tubules of the testes
C) In the epididymis
D) Throughout the male reproductive tract

A

B) Within the seminiferous tubules of the testes

55
Q

What is the first step in spermatogenesis?
A) The differentiation of primary spermatocytes into spermatids
B) The proliferation and differentiation of spermatogonia by mitosis
C) The meiotic division of spermatogonia
D) Spermiogenesis

A

B) The proliferation and differentiation of spermatogonia by mitosis

56
Q

How many spermatids are produced from one primary spermatocyte?
A) One
B) Two
C) Four
D) Eight

A

C) Four

Primary spermatocytes, which are diploid, then undergo two meiotic divisions to produce four haploid spermatids.

57
Q

What is spermiogenesis?
A) The division of spermatogonia into spermatocytes
B) The process where spermatids mature into motile spermatozoa
C) The initial phase of spermatogenesis in the testes
D) The movement of mature sperm through the female reproductive tract

A

B) The process where spermatids mature into motile spermatozoa

58
Q

Where do spermatozoa gain the capacity for motility?
A) In the seminiferous tubules
B) In the epididymis
C) During their journey through the female reproductive tract
D) After ejaculation

A

B) In the epididymis

59
Q

How long does the process of spermatogenesis typically take?
A) About 28 days
B) About 72 days
C) About 9 months
D) About 48 hours

A

B) About 72 days

60
Q

Where are mature sperm stored until ejaculation?
A) In the seminiferous tubules
B) In the caudal portion of the epididymis
C) In the vas deferens
D) In the prostate gland

A

B) In the caudal portion of the epididymis

61
Q

What is essential for maintaining optimum sperm function during storage?
A) High levels of estrogen
B) Adequate levels of testosterone
C) Low levels of progesterone
D) Constant exposure to cold temperatures

A

B) Adequate levels of testosterone

62
Q

What can lead to fertility issues or infertility in men?
A) Hypergonadism, characterized by excessive testosterone production
B) Hypogonadism, characterized by insufficient testosterone production
C) Excessive cooling of the scrotum
D) High levels of physical activity

A

B) Hypogonadism, characterized by insufficient testosterone production

63
Q

Why must the scrotum be kept at a temperature slightly lower than normal internal body temperature for sperm viability?
A) To increase the production of testosterone
B) To reduce the risk of infections
C) To prevent overheating and damage to sperm function and viability
D) To enhance the speed of sperm motility

A

C) To prevent overheating and damage to sperm function and viability

64
Q

Which factor is important to consider in cases of male infertility related to sperm function?
A) High altitude living conditions
B) Dietary preferences
C) Environmental factors and lifestyle, such as occupation and heat exposure
D) Frequency of exercise

A

C) Environmental factors and lifestyle, such as occupation and heat exposure

65
Q

Where do primordial germ cells (PGCs) originate in an embryo?
A) In the genital ridge
B) In the dorsal mesentery of the hindgut
C) Inside the seminiferous tubules of the testes
D) In the lumen of the seminiferous tubules
Answer: B) In the dorsal mesentery of the hindgut

A

B) In the dorsal mesentery of the hindgut

66
Q

What is the destination of PGCs after they migrate during embryonic development?
A) The dorsal mesentery
B) The primitive gonads
C) The seminiferous tubules
D) The Sertoli cells

A

B) The primitive gonads

67
Q

Into what do PGCs transform once they reach the gonads?
A) Primary spermatocytes
B) Spermatogonia
C) Secondary spermatocytes
D) Spermatids

A

B) Spermatogonia

68
Q

At what stage do some spermatogonia develop into primary spermatocytes?
A) Immediately upon reaching the gonads
B) During fetal development
C) When the individual reaches puberty
D) After the first meiotic division

A

C) When the individual reaches puberty

69
Q

What triggers the development of primary spermatocytes into further stages?
A) Physical maturity
B) Exposure to high temperatures
C) Hormonal signals during adolescence
D) Completion of spermiogenesis

A

C) Hormonal signals during adolescence

70
Q

What is the result of the first meiotic division of primary spermatocytes?
A) They become spermatogonia
B) They transform into spermatids
C) They develop into secondary spermatocytes
D) They mature into spermatozoa

A

C) They develop into secondary spermatocytes

71
Q

What follows the second meiotic division of secondary spermatocytes?
A) Formation of primary spermatocytes
B) Return to the spermatogonial stage
C) Production of haploid spermatids
D) Immediate transformation into mature spermatozoa

A

C) Production of haploid spermatids

72
Q

During which process do spermatids transform into mature spermatozoa?
A) Spermatogenesis
B) Spermiogenesis
C) Spermiation
D) Mitosis

A

B) Spermiogenesis

Spermiogenesis is the transformation phase in which spermatids mature into spermatozoa (sperm cells).

73
Q

What is spermiation in the context of spermatogenesis?
A) The initial development of spermatogonia
B) The meiotic division of primary spermatocytes
C) The release of mature spermatozoa into the seminiferous tubule lumen
D) The process of spermatids maturing into spermatozoa

A

C) The release of mature spermatozoa into the seminiferous tubule lumen

Spermiogenesis concludes with spermiation, the process where mature spermatozoa are released from the Sertoli cells into the lumen of the seminiferous tubules. This release marks the end of sperm maturation, and these cells are now ready to embark on their journey through the male and female reproductive tracts in pursuit of fertilizing an ovum.

74
Q

Where does oogenesis take place within the female body?
A) In the endometrium of the uterus
B) In the cortex of the ovary
C) In the fallopian tubes
D) In the seminiferous tubules

A

B) In the cortex of the ovary

75
Q

How does oogenesis begin in terms of cell division?
A) By meiosis of the oogonia
B) By mitosis of the primordial follicles
C) By mitosis transforming oogonia into primary oocytes
D) By the direct transformation of oogonia into secondary oocytes

A

C) By mitosis transforming oogonia into primary oocytes

76
Q

At what stage are primary oocytes arrested until puberty?
A) Metaphase I
B) Prophase I, specifically the diplotene stage
C) Anaphase II
D) Telophase I

A

B) Prophase I, specifically the diplotene stage

77
Q

What significant event occurs with the primary oocyte at puberty?
A) It undergoes mitosis to produce more primary oocytes
B) It completes meiosis I to form a secondary oocyte and a polar body
C) It directly transforms into an ovum
D) It disintegrates if not fertilized

A

B) It completes meiosis I to form a secondary oocyte and a polar body

78
Q

How does oogenesis differ from spermatogenesis in terms of cell division outcomes after meiosis I?
A) Oogenesis produces more gametes than spermatogenesis
B) Oogenesis results in one secondary oocyte and one polar body, while spermatogenesis produces four spermatids
C) Oogenesis leads to the formation of four oocytes
D) Spermatogenesis results in only one sperm cell from each primary spermatocyte

A

B) Oogenesis results in one secondary oocyte and one polar body, while spermatogenesis produces four spermatids

79
Q

What happens to the secondary oocyte during meiosis II?
A) It is arrested in metaphase II until fertilization occurs
B) It immediately completes meiosis II to form an ovum
C) It divides into four new oocytes
D) It transforms into a polar body

A

A) It is arrested in metaphase II until fertilization occurs

80
Q

What is the fate of polar bodies in oogenesis?
A) They develop into oocytes
B) They are fertilized and develop into embryos
C) They generally disintegrate after serving their chromosomal segregation purpose
D) They are stored in the ovary for future fertilization

A

C) They generally disintegrate after serving their chromosomal segregation purpose

81
Q

What occurs if fertilization of the secondary oocyte takes place?
A) Meiosis II is completed, resulting in the formation of an ootid which matures into an ovum
B) The oocyte returns to the diplotene stage of prophase I
C) It undergoes mitosis to produce more secondary oocytes
D) The secondary oocyte immediately disintegrates

A

A) Meiosis II is completed, resulting in the formation of an ootid which matures into an ovum

82
Q

When does follicular development begin?
A) After birth
B) In utero and continues throughout reproductive years
C) At puberty
D) During menopause

A

B) In utero and continues throughout reproductive years

83
Q

How long does the transition from a primary follicle to ovulation typically take?
A) 72 days
B) 85 days
C) 28 days
D) 14 days

A

B) 85 days

The transition from a primary follicle to ovulation spans approximately 85 days, compared to the 72 days required for spermatogenesis.

84
Q

What is the early stage of follicular development characterized by?
A) Dependence on gonadotropins
B) Rapid cellular division
C) Independence from gonadotropins
D) Immediate maturation to the antral stage

A

C) Independence from gonadotropins

85
Q

What factors influence the number of follicles that mature during each menstrual cycle?
A) The amount of Progesterone available
B) The number of primordial cells
C) The amount of Follicle Stimulating Hormone (FSH) and follicle sensitivity to gonadotropins
D) The phase of the menstrual cycle

A

C) The amount of Follicle Stimulating Hormone (FSH) and follicle sensitivity to gonadotropins

86
Q

What happens to the cohort of follicles recruited during the follicular progression?
A) All follicles mature into ova
B) Most undergo atresia, with typically one becoming the dominant follicle
C) They all become antral follicles
D) Each follicle is fertilized

A

B) Most undergo atresia, with typically one becoming the dominant follicle

87
Q

What occurs after the dominant follicle matures during the menstrual cycle?
A) It undergoes atresia
B) It matures into the ovum and is released during ovulation
C) It remains in the ovary until menopause
D) It transforms back into a primary follicle

A

B) It matures into the ovum and is released during ovulation

88
Q

What is the consequence if the mature ovum is not fertilized after ovulation?
A) It develops into a secondary oocyte
B) It is stored in the fallopian tube for the next cycle
C) It resumes development
D) It disintegrates

A

D) It disintegrates

89
Q

At what age do women typically experience menopause, and what does it signify?
A) Around 30-35 years old, marking the peak of reproductive ability
B) Around 40-45 years old, indicating the start of reproductive decline
C) Around 50-51 years old, marking the end of the reproductive years
D) Around 60-65 years old, coinciding with andropause in men

A

C) Around 50-51 years old, marking the end of the reproductive years

Women typically experience menopause around 50-51 years old, marking the end of the reproductive years as ovarian function declines and menstrual cycles cease.

Men experience a more gradual decline in reproductive function known as andropause, around 60-65 years old, characterized by a decrease in testosterone levels, which affects spermatogenesis.

90
Q

What is andropause and when does it typically occur in men?
A) The peak of testosterone production, occurring around 30 years old
B) The beginning of spermatogenesis, occurring at puberty
C) The decline in reproductive function, occurring around 60-65 years old
D) The increase in sperm motility, happening in late adulthood

A

C) The decline in reproductive function, occurring around 60-65 years old

Women typically experience menopause around 50-51 years old, marking the end of the reproductive years as ovarian function declines and menstrual cycles cease.

Men experience a more gradual decline in reproductive function known as andropause, around 60-65 years old, characterized by a decrease in testosterone levels, which affects spermatogenesis.

91
Q

What is the function of the Hypothalamo-Pituitary-Ovarian (HPO) Axis?
A) To regulate blood sugar levels
B) To control the menstrual cycle
C) To manage the immune response
D) To regulate body temperature

A

B) To control the menstrual cycle

92
Q

How does the hypothalamus influence the menstrual cycle?
A) By secreting estrogen and progesterone
B) Through the release of Gonadotropin-Releasing Hormone (GnRH)
C) By producing follicles in the ovary
D) Through the direct release of Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH)

A

B) Through the release of Gonadotropin-Releasing Hormone (GnRH)

93
Q

What role do FSH and LH play in the menstrual cycle?
A) They trigger the release of GnRH from the hypothalamus
B) They stimulate follicular development in the ovary
C) They cause the uterus to shed its lining
D) They are responsible for the menstrual phase

A

B) They stimulate follicular development in the ovary

94
Q

What happens to the dominant follicle if fertilization does not occur?
A) It remains in the ovary for the next cycle
B) It transforms into the corpus luteum
C) It disintegrates immediately
D) It develops into a mature ovum

A

B) It transforms into the corpus luteum

95
Q

What hormone is primarily produced by the corpus luteum during the luteal phase?
A) Estrogen
B) Testosterone
C) Progesterone
D) Follicle-Stimulating Hormone (FSH)

A

C) Progesterone

96
Q

What triggers the start of a new menstrual cycle?
A) The increase of progesterone and estrogen
B) The continuous presence of the corpus luteum
C) The reduction of steroid hormones and increased production of GnRH, FSH, and LH
D) The implantation of an embryo in the uterine lining

A

C) The reduction of steroid hormones and increased production of GnRH, FSH, and LH

97
Q

What occurs if fertilization of the dominant follicle happens?
A) The menstrual cycle starts over immediately
B) The corpus luteum disintegrates quickly
C) Estradiol and progesterone levels remain elevated to support embryo development
D) FSH and LH levels continue to rise

A

C) Estradiol and progesterone levels remain elevated to support embryo development

98
Q

How long does the corpus luteum function in sustaining pregnancy before the placenta takes over?
A) 2-4 weeks
B) 8-9 weeks
C) 12-14 weeks
D) 20-24 weeks

A

B) 8-9 weeks

Role of the Corpus Luteum in Pregnancy:

The corpus luteum becomes the corpus luteum of pregnancy, vital for sustaining the pregnancy in its early weeks.
It continues to produce hormones until the placenta fully develops and takes over this function, usually around 8-9 weeks of gestation.

99
Q

When do primordial germ cells start migrating to the genital ridge?
A) At birth
B) During puberty
C) In fetal life
D) At menopause

A

C) In fetal life

100
Q

What happens between 6-8 weeks of gestation?
A) The peak oogonal content is reached
B) Ovarian differentiation begins with rapid mitotic multiplication of germ cells
C) Primary oocytes reduce to 1-2 million
D) The onset of puberty

A

B) Oogonia transform into oocytes and enter the first meiotic division

101
Q

At what stage do oocytes arrest during fetal development?
A) Metaphase II of Meiosis II
B) Prophase I of Meiosis I
C) Anaphase of Meiosis II
D) Telophase of Meiosis I

A

B) Ovarian differentiation begins with rapid mitotic multiplication of germ cells

102
Q

At 11-12 weeks of gestation, what significant change occurs in oogonia?
A) They differentiate into primary oocytes and arrest at Prophase I
B) They reach their peak content
C) They migrate to the genital ridge
D) They are depleted leading to menopause

A

A) They differentiate into primary oocytes and arrest at Prophase I

103
Q

How many primary oocytes are typically present at birth?
A) 300,000-500,000
B) 1-2 million
C) 6-7 million
D) A few hundred

A

B) 1-2 million

16-20 Weeks of Gestation:

Peak oogonal content reaches 6-7 million, establishing the fixed initial endowment for life.

104
Q

How does the germ cell mass change by the onset of puberty?
A) Increases to 6-7 million
B) Reduces to 300,000-500,000 units
C) Remains the same as at birth
D) Decreases to a few hundred

A

B) Reduces to 300,000-500,000 units

105
Q

Throughout the reproductive lifespan, how many oocytes are typically selected for ovulation?
A) 1-2 million
B) 6-7 million
C) 400-500
D) 300,000-500,000

A

C) 400-500

106
Q

What process contributes to follicular loss during each menstrual cycle?
A) Ovulation of multiple oocytes
B) Conversion of oocytes into primary follicles
C) Atresia of the non-dominant follicles
D) Continuous division of primary oocytes

A

C) Atresia of the non-dominant follicles

107
Q

What characterizes the perimenopausal phase regarding follicular count?
A) Rapid increase in the number of follicles
B) Stabilization of the follicular pool
C) Acceleration in follicular loss leading to depletion
D) Initiation of new follicle formation

A

C) Acceleration in follicular loss leading to depletion

Perimenopause:

There is an acceleration in follicular loss.
The follicular pool becomes depleted, leading to menopause when only a few hundred follicles remain.

108
Q

What defines a primordial follicle?
A) An oocyte in the metaphase stage of meiosis II
B) An oocyte arrested in the prophase stage of meiosis I, surrounded by pregranulosa cells
C) A fully mature oocyte ready for fertilization
D) A secondary oocyte undergoing the second meiotic division

A

B) An oocyte arrested in the prophase stage of meiosis I, surrounded by pregranulosa cells

109
Q

How do pregranulosa cells change in the transition to a primary follicle?
A) They decrease in number
B) They remain spindle-shaped
C) They transform into a cuboidal layer of granulosa cells
D) They become fluid-filled cavities

A

C) They transform into a cuboidal layer of granulosa cells

110
Q

What is the characteristic feature of a pre-antral follicle?
A) The presence of a single layer of spindle-shaped cells
B) The formation of a fluid-filled cavity known as the antrum
C) Further proliferation of granulosa cells
D) The completion of meiosis I by the oocyte

A

C) Further proliferation of granulosa cells

111
Q

At which stage do follicles become gonadotropin dependent?
A) Primordial follicle stage
B) Primary follicle stage
C) Pre-antral follicle stage
D) Antral follicle stage

A

C) Pre-antral follicle stage

112
Q

What is the significance of the antrum in an antral follicle?
A) It signifies the completion of meiosis II.
B) It indicates the follicle is ready for fertilization.
C) It is a fluid-filled cavity that forms as the follicle grows.
D) It shows that the follicle is still in a gonadotropin-independent phase.

A

C) It is a fluid-filled cavity that forms as the follicle grows.

113
Q

Why are gonadotropins important for the progression of antral follicles?
A) They decrease the number of granulosa cells
B) They stimulate the follicle to grow and the oocyte to mature
C) They arrest the oocyte in the prophase stage of meiosis I
D) They initiate the formation of the primordial follicle

A

B) They stimulate the follicle to grow and the oocyte to mature

114
Q

Where typically does fertilization occur?
A) In the uterus
B) In the ovary
C) In the fallopian tube
D) In the peritoneal cavity

A

C) In the fallopian tube

115
Q

When is fertilization considered complete?
A) When the sperm enters the ovum
B) After the zygote begins its first cell division
C) When the male and female pronuclei fuse and the diploid chromosome number is restored
D) Once the zygote implants in the uterus

A

C) When the male and female pronuclei fuse and the diploid chromosome number is restored

116
Q

What are the two key changes that sperm undergo during their transport to the fallopian tube?
A) Mitosis and meiosis
B) Capacitation and acrosome reaction
C) Fertilization and division
D) Maturation and differentiation

A

B) Capacitation and acrosome reaction

117
Q

How does the sperm find the mature ovum?
A) Through random movement in the fallopian tube
B) By following the temperature gradient in the female reproductive tract
C) Through a process called chemotaxis, where it is attracted to the ovum
D) By the mechanical guidance of cilia in the fallopian tubes

A

C) Through a process called chemotaxis, where it is attracted to the ovum

118
Q

Where does fertilization typically occur within the female reproductive tract?
A) In the ovary
B) In the cervix
C) In the ampullary portion of the fallopian tube
D) In the uterus

A

C) In the ampullary portion of the fallopian tube

119
Q

How many days post-fertilization does the zygote typically form a morula?
A) 1 to 3 days
B) 3 to 5 days
C) 5 to 7 days
D) Over a week

A

A) 1 to 3 days

120
Q

What significant event occurs between days 3 to 5 post-fertilization?
A) Formation of the zygote
B) Transition of the morula to an early blastocyst
C) The blastocyst implants in the uterine wall
D) The embryo completes its journey through the fallopian tube

A

B) Transition of the morula to an early blastocyst

  • Development into Blastocyst:
    • By days 3 to 5, fluid accumulation within the morula leads to the formation of an early blastocyst.
    • The blastocyst differentiates into a structure with around 58 cells, including a 5-cell inner cell mass (destined to become the embryo) and 53 trophoblastic cells (future part of the placenta).
121
Q

What is the first cell division timeline post-fertilization?
A) Less than 10 hours
B) About 20 hours
C) 48 hours
D) 72 hours

A

B) About 20 hours

122
Q

Where does the cell cleavage of the zygote to form a morula and then a blastocyst occur?
A) In the uterus
B) In the fallopian tube
C) In the ovary
D) Outside the female body

A

B) In the fallopian tube

123
Q

During its transition from the fallopian tube to the uterine cavity, what does the blastocyst release to facilitate implantation?
A) Estrogen and progesterone
B) Blood cells and nutrients
C) Cytokines and proteases
D) Oxygen and carbon dioxide

A

C) Cytokines and proteases

124
Q

What is apposition in the context of embryonic development?
A) The zygote divides to form the morula
B) The blastocyst firmly embeds into the endometrial lining
C) The loose attachment of the blastocyst to the endometrial lining
D) The sperm penetrates the egg

A

C) The loose attachment of the blastocyst to the endometrial lining

125
Q

Where does implantation of the blastocyst occur?
A) In the fallopian tube
B) In the endometrial cavity of the uterus
C) On the outer surface of the ovary
D) In the cervical canal

A

B) In the endometrial cavity of the uterus

126
Q

What significant event follows the implantation of the blastocyst?
A) Return of the blastocyst to the fallopian tube
B) The embryo develops primary germ layers and begins organogenesis
C) The blastocyst splits to form identical twins
D) The uterus starts to shrink

A

B) The embryo develops primary germ layers and begins organogenesis

127
Q
A

OB1 (5 decks)

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