286478
Which of the following is the first change that occurs to the zygote after fertilization?
1 It divides to form a hollow ball of cells, called the blastocyst.
2 It begins to secrete the hormones.
3 It contacts the endometrial wall of the uterus and becomes buried inside it.
4 It initiates the formation of a placenta.
Explanation:
(a) The zygote divides mitotically to form 8,16 daughter cells called blastomeres. This stage is called morula which continues to divide and transforms into blastocyst.
NCERT Page-52 & 53 / N-35
Human Reproduction(NCERT)
286479
Presence of $XX$ or $XY$ chromosomes in zygote depends on
1 the sperm carrying $X$ chromosome fertilized the ovum.
2 the sperm carrying $Y$ chromosome fertilized the ovum.
3 the sperm without any chromosome fertilized the ovum.
4 the sperm carrying $X$ or $Y$ chromosomes fertilized the ovum.
Explanation:
(d) Ovum contains the haploid set of chromosomes with one of the $X$ chromosomes. The haploid set of chromosomes in the male gamete, sperm has either the $X$ or $Y$ chromosome. Thus, the sex of the foetus depends on the male gamete fertilizing the ovum.
NCERT Page-52 / N-36
Human Reproduction(NCERT)
286480
In the given figure the structure of ovum is surrounded by few sperms and some art are labelled as A, B, C and D.
Which of the following options shows the correct labelling?
1 A $\to $ Zona pellucida; B $\to $ Ovuin'; $\text{C}\to $ Cells of corona radiata, $D\to $ Perivitelline space
286478
Which of the following is the first change that occurs to the zygote after fertilization?
1 It divides to form a hollow ball of cells, called the blastocyst.
2 It begins to secrete the hormones.
3 It contacts the endometrial wall of the uterus and becomes buried inside it.
4 It initiates the formation of a placenta.
Explanation:
(a) The zygote divides mitotically to form 8,16 daughter cells called blastomeres. This stage is called morula which continues to divide and transforms into blastocyst.
NCERT Page-52 & 53 / N-35
Human Reproduction(NCERT)
286479
Presence of $XX$ or $XY$ chromosomes in zygote depends on
1 the sperm carrying $X$ chromosome fertilized the ovum.
2 the sperm carrying $Y$ chromosome fertilized the ovum.
3 the sperm without any chromosome fertilized the ovum.
4 the sperm carrying $X$ or $Y$ chromosomes fertilized the ovum.
Explanation:
(d) Ovum contains the haploid set of chromosomes with one of the $X$ chromosomes. The haploid set of chromosomes in the male gamete, sperm has either the $X$ or $Y$ chromosome. Thus, the sex of the foetus depends on the male gamete fertilizing the ovum.
NCERT Page-52 / N-36
Human Reproduction(NCERT)
286480
In the given figure the structure of ovum is surrounded by few sperms and some art are labelled as A, B, C and D.
Which of the following options shows the correct labelling?
1 A $\to $ Zona pellucida; B $\to $ Ovuin'; $\text{C}\to $ Cells of corona radiata, $D\to $ Perivitelline space
286478
Which of the following is the first change that occurs to the zygote after fertilization?
1 It divides to form a hollow ball of cells, called the blastocyst.
2 It begins to secrete the hormones.
3 It contacts the endometrial wall of the uterus and becomes buried inside it.
4 It initiates the formation of a placenta.
Explanation:
(a) The zygote divides mitotically to form 8,16 daughter cells called blastomeres. This stage is called morula which continues to divide and transforms into blastocyst.
NCERT Page-52 & 53 / N-35
Human Reproduction(NCERT)
286479
Presence of $XX$ or $XY$ chromosomes in zygote depends on
1 the sperm carrying $X$ chromosome fertilized the ovum.
2 the sperm carrying $Y$ chromosome fertilized the ovum.
3 the sperm without any chromosome fertilized the ovum.
4 the sperm carrying $X$ or $Y$ chromosomes fertilized the ovum.
Explanation:
(d) Ovum contains the haploid set of chromosomes with one of the $X$ chromosomes. The haploid set of chromosomes in the male gamete, sperm has either the $X$ or $Y$ chromosome. Thus, the sex of the foetus depends on the male gamete fertilizing the ovum.
NCERT Page-52 / N-36
Human Reproduction(NCERT)
286480
In the given figure the structure of ovum is surrounded by few sperms and some art are labelled as A, B, C and D.
Which of the following options shows the correct labelling?
1 A $\to $ Zona pellucida; B $\to $ Ovuin'; $\text{C}\to $ Cells of corona radiata, $D\to $ Perivitelline space
NEET Test Series from KOTA - 10 Papers In MS WORD
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Human Reproduction(NCERT)
286478
Which of the following is the first change that occurs to the zygote after fertilization?
1 It divides to form a hollow ball of cells, called the blastocyst.
2 It begins to secrete the hormones.
3 It contacts the endometrial wall of the uterus and becomes buried inside it.
4 It initiates the formation of a placenta.
Explanation:
(a) The zygote divides mitotically to form 8,16 daughter cells called blastomeres. This stage is called morula which continues to divide and transforms into blastocyst.
NCERT Page-52 & 53 / N-35
Human Reproduction(NCERT)
286479
Presence of $XX$ or $XY$ chromosomes in zygote depends on
1 the sperm carrying $X$ chromosome fertilized the ovum.
2 the sperm carrying $Y$ chromosome fertilized the ovum.
3 the sperm without any chromosome fertilized the ovum.
4 the sperm carrying $X$ or $Y$ chromosomes fertilized the ovum.
Explanation:
(d) Ovum contains the haploid set of chromosomes with one of the $X$ chromosomes. The haploid set of chromosomes in the male gamete, sperm has either the $X$ or $Y$ chromosome. Thus, the sex of the foetus depends on the male gamete fertilizing the ovum.
NCERT Page-52 / N-36
Human Reproduction(NCERT)
286480
In the given figure the structure of ovum is surrounded by few sperms and some art are labelled as A, B, C and D.
Which of the following options shows the correct labelling?
1 A $\to $ Zona pellucida; B $\to $ Ovuin'; $\text{C}\to $ Cells of corona radiata, $D\to $ Perivitelline space
