Answer to question 1
A= Centromere (MTOC with centrioles).
B= Chromosome aligned on middle plate.
C= Astral microtubules
D= Kinetochore microtubules
E= Polar microtubules.
3. D (kinetochore microtubules)
4. B (Chromosome)
5. A (centrioles)
Answer to question 2
Cytology refers to the study of cell such as cell morphology, physiology etc. As we know all cells with some exceptions undergoes cell division in order to multiply. Cell undergoing cell division transit through various morphological changes along with it there is change in cellular components such as genetic content, proteins, cell organelles etc.
A normal cell can divide by two process one is Mitotic cell division while the second one known as Meiosis.
Meiosis: this is also referred as reductional division as the daughter cells produced by meiosis have half the ploidy as that of mother cell. Meiosis cell division produces the four daughter cells. For example, If any (2n) cell undergoes meiosis and produced four daughter cell then each daughter cell would have (n) ploidy level.
Stages of meiosis: meiosis cell division is divided into two Meiosis I and Meiosis II, Meiosis I is called reductional division in which the crossing over even occurs and reduces the number of chromosomes in daughter cell whereas, Meiosis II is just like the normal mitosis.
In meiosis I prophase stage is divided into four
- Diplotene and
The cross over event occur in the Pachytene stage where there is exchange of chromatin material between two homologous chromosomes and there is chiasmata formation occurs. All these events are termed as cross-over events which lead to the recombination of the genetic material between the segments of two chromosomes. This cross over lead to different in genetic variation in the daughter cells which do not take place in mitosis.
Hence, option D) would be the right answer.
Answer to question 3
Answer :-21) the image above is a slide of
Answer to question 4
Answer-23) the muscle tissue in above image shows
Muscle tissue are of three types
1)Smooth muscle : occurs in walls of internal organs
– has spindle shaped ,nonstriated , uninucleated fibres
– it is involuntary by action.
2) Cardiac muscle : occurs in walls of heart.
– has striated ,branched non nucleated fibres
– involuntary by action
3) skeletal muscle : attached to skeleton.
-striated , tubular and multinucleated fibres.
– voluntary by action.