Tag: division for growth and reproduction

Questions Related to division for growth and reproduction

"Genes in somatic cells undergo mutation with time and cause senescence. This theory belongs to ________________.

different stages of growth reproductive system in humans division for growth and reproduction human system biology

  1. Error and damage theories

  2. Hormonal theory

  3. Immunological theories

  4. Programmed senescence theory

Show answer
Correct Option: A
Explanation:

A. Error and damage theories - emphasize environmental assaults to living organisms that induce cumulative damage at various levels as the cause of aging.

B. Hormonal theory - hormones or reduced production of hormones might cause aging has also led some to believe that they could be an anti-aging elixir. 

C. Immunological theory - asserts that the process of human aging is, in fact, a mild and generalized form of prolonged auto-immune phenomenon.

D. Programmed senescence theory - refers to the idea that senescence in humans and other organisms is purposely caused by evolved biological mechanisms in order to obtain an evolutionary advantage.

So, the correct option is ‘Error and damage theories’.

The sperms that are not ejaculated are reabsorbed in the-

different stages of growth reproductive system in humans division for growth and reproduction human system biology

  1. Corpus epididymis

  2. Cauda epididymis

  3. caput epididymis

  4. Vas deferens

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Correct Option: A
Explanation:
If a man has an inactive sex life and can’t even be bothered to pleasure himself, sperm that stores up inside his body without being released will eventually die and be reabsorbed into his body like so much horse manure spread judiciously throughout a cornfield.
So the correct option is ' Corpus epididymis'.

Cell cycle was divided into  four stages i.e. G$ _1$, S, G$ _2$, M by

biology division for growth and reproduction cell membrane and cell wall cell wall cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. W. Flemming

  2. Strass burger

  3. Howard and Pelc

  4. Farmer

Show answer
Correct Option: C
Explanation:

Howard and Pelc divided cell cycle in four stage. The cell cycle is an ordered set of events, culminating in cell growth and division into two daughter cells. Non-dividing cells not considered to be in the cell cycle. The stages  are G$ _1$-S-G$ _2$-M. The G$ _1$ stage stands for "GAP 1". The S stage stands for "Synthesis". This is the stage when DNA replication occurs. The G$ _2$ stage stands for "GAP 2". The M stage stands for "mitosis", and is when and cytoplasmic division occur.

Cell division is tightly regulated, which of the following is true regarding mitosis or meiosis.
I. Mitosis shows no homologous pairing.
II. There is no S phase between meiosis I and II.
III. Meiosis centromeres do not divide at anaphase I.

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. I and III only

  2. I and II only

  3. II only

  4. I, II and III

Show answer
Correct Option: D
Explanation:

Homologous pairing occurs in meiosis when homologous chromosomes come closer and synapsis occur leading to homologous pairing.

S phase occurs between G1 and G2 phase not between meiosis1 and meiosis2.
At anaphase I, sister chromatids remain attached to their centromeres, so they do not divide at this stage.
So the correct option is 'I, II and III'

Which of the following can not be used to differentiate meiosis with mitosis?

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. Replication of chromosome before division

  2. Exchange of genetic material

  3. Formation of tetrad

  4. $2$ & $3$ both

Show answer
Correct Option: A
Explanation:

Answer is A. Replication of chromosome some before division

can not be used to differentiate meiosis with mitosis because it is the process which is done in interphase. And interphase are same in both meiosis and mitosis. 

A cell in mitotic prophase can be distinguished from a cell in meiotic prophase by?

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. Formation of tetrad in a meiotic cell

  2. The terminalisation of chiasmata in late prophase of mitosis

  3. Zipping in early prophase of mitosis

  4. Presence of only half as many chromosomes in the meiotic cell

Show answer
Correct Option: A
Explanation:

The formation of tetrad is a special characteristic of Prophase 1 of meiosis 1.

The homologous pair aligns with each other and gets ready for crossing over.
So, the correct option is 'Formation of tetrad in a meiotic cell'.

The basic difference between mitosis and meiosis is that

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. Homologous chromosomes form tetrads in mitosis but not in meiosis

  2. Homologous chromosomes form tetrads in meiosis but not in mitosis

  3. The nuclear membrane disappears in mitosis but not in meiosis

  4. A spindle forms in mitosis but not in meiosis

  5. A spindle forms in meiosis but not in mitosis

Show answer
Correct Option: B
Explanation:
  • The pairing of homologous chromosomes during the zygotene of prophase I and formation of tetrads are characteristic of meiosis; not mitosis. 
  • Both mitosis and meiotic divisions exhibit the disappearance of the nuclear membrane and spindle formation.

  •  So, the correct answer is B. 

Which of the following is unique to mitosis and not a part of meiosis? 

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. Homologous chromosomes behave independently

  2. Chromatids are separated during anaphase

  3. Homologous chromosomes pair and form bivalents

  4. Homologous chromosomes crossover

Show answer
Correct Option: A
Explanation:

Mitosis and meiosis are the two types of cell division which occur in a living cell. The meiosis is characterized by the pairing of homologous chromosomes, crossing over and separation of homologous chromosomes. Because the homologous chromosomes separate, the chromosome number is reduced to one-half during meiosis. In mitosis, the homologous chromosomes do not pair or exchange segments. There is no separation of homologous chromosomes consequently the chromosome number is not reduced. The homologous chromosomes remain separate or independent throughout mitosis.

So, the correct answer is option A.

Meiosis I is reduction division. Meiosis II is equational division due to 

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. Separation of chromatids

  2. Crossing over

  3. Pairing of homologous chromosomes

  4. Disjunction of homologous chromosomes

Show answer
Correct Option: A
Explanation:

Meiosis is a reduction division because the end result of this special type of cell division is four haploid cells. The first meiotic division occurs which results in two cells, each with 46 chromosomes. Then, the second round of meiotic division occurs and each of these two cells divides resulting in four haploid cells. 

In meiosis II, the two chromatids of each chromosome separate from each other and go to separate daughter cells. As a result, the number of chromosomes remains the same as produced by meiosis I. Therefore, meiosis II is also called as homotypic or equational division.  
So, the correct answer is option A.

Which of the following is a correct comparison between mitosis and meiosis?

botany division for growth and reproduction difference between meiosis and mitosis meiosis the origin of cells and cell division

  1. Meiosis II resembles mitosis when sister chromatids split

  2. Both prophase of mitosis and meiosis include pairing up of homologous chromosomes

  3. In mitosis, aligning of maternal and paternal chromosomes can be random whereas, in meiosis, the alignment is fixed

  4. Replication of chromosomes occurs at the start of mitosis and meiosis during prophase

Show answer
Correct Option: A
Explanation:

Meiosis II is similar to Mitosis as sister chromatids of the haploid set of chromosomes split during Anaphase II of Meiosis II. 

So, the correct answer is 'Meiosis II resembles mitosis when sister chromatids split'