9th Class Biology Chapter 5 Short Questions with Answers Solved

Question: 1

Define Meiosis.

Answer: 1

1-131

Meiosis is the process by which one diploid eukaryotic cell divide to generate four haploid daughter cells. It usually happens during gamete formation.

Question: 2

What is synapsis?

Answer: 2

2-131

The homologous chromosomes line up with each other and form pairs by process called synapsis

Question: 3

Differentiate between diploid and Haploid cells.

Answer: 3

3-131

Diploid: It means the cells in which chromosomes are in pairs. Example: in somatic cells.

Question: 4

What is S-phase?

Answer: 4

4-131

In this phase, cell duplicates its chromosomes. As a result each chromosome consists of two sister chromatids

Question: 5

Differentiate mitosis and Meiosis.

Answer: 5

5-131

Mitosis:i .It takes place in somatic cells. ii. It results in two duaughter cells. iii. No crossing over takes place. iv. No of chromosome remain same as parent cell

Question: 6

What is metastasis? Write its role in cancer.

Answer: 6

6-131

The process, in which malignant cells send the cancer cells to other parts of body

Question: 7

Define Anabolism ?

Answer: 7

7-131

Anabolism include all those biochemical reaction in which large molecule are formed from small molecules. Energy is used in anabolism.

Question: 8

What is metaphase plate?

Answer: 8

8-131

The chromosomes arrange in cell equator and form a plate called as metaphase plate.

Question: 9

Describe G1 phase.

Answer: 9

9-131

After production, cell starts cell cycle with G1 phase. During Gq1, cell increases its supply of proteins, increases number of its organelles and grow in size. This is marked by synthesis of enzymes which are required in next place.

Question: 10

What is crossing over? Give its one benefit

Answer: 10

10-131

Crossing over. The non-sister chromatids of hmologous chromosomes exchange their segments and teh phenomenon is known as crossing over. Benefit. It is the main source of variations. 2. It is necessary to maintain no of chromosome in next generation.

Question: 11

Name the phases of karyokinesis?

Answer: 11

11-131

Prophase
Metaphase
Anaphase
Telophase

Question: 12

Define Chiasmata.

Answer: 12

12-131

Chiasmata: During meiosis the two non -sister chromatids of homologous chromosomes join each other at certain points along their length. These points of attachment are called chiasmata.

Question: 13

How is mitosis significant?

Answer: 13

13-131

Importance of mitosis is the maintenance of chromosomal set i.e. each daughter cell receives chromosomes that are alike in composition and equal in number to the chromosome of parent cell. During the occasions of development and growth, cell replacement, regeneration and asexual reproduction, mitosis happens.

Question: 14

Name two phases of cell cycle ?

Answer: 14

14-131

Interphase
Mitotic phase or M-phase

Question: 15

Write characteristic features of telophase II.

Answer: 15

15-131

Telophase II is marked with uncoiling and disappearance of chromosomes ,Nuclear envelop reform, cleavage or cell wall formation eventually produce a total 4 daughter cells each with haploid set of chromosome.

Question: 16

What is interphase?

Answer: 16

16-131

The time when a cell's metabolic activity is very high is called interphase. It has 3 phase G1 Phase , G2 phase, S-Phase

Question: 17

What is benign tumor ?

Answer: 17

17-131

If tumors remain in their original location for a long time they are called benign tumors

Question: 18

Define Cell cycle.

Answer: 18

18-131

The series of events occurring in cell from time cell is produced until it completes mitosis and produces new cells. It has 2 phase. Interphase, Mitotic phase

Question: 19

What is binary fission?

Answer: 19

19-131

It is a process in which one organism divide into two organism

Question: 20

S-Phase of interphase is important and cell can never divide without it justify.

Answer: 20

20-131

In S-phase the cell duplicates its chromosomes the DNA molecules of each chromosome is copied and new protein molecules are attached the result is that each chromosome consists of two sister chromatids, which contains identical genes. In the absence of a S-Phase no replication of DNA will result in absence of chromosomes with two sister chromatids . Hence cell division will not occur

Question: 21

Define Mitotic phase ?

Answer: 21

21-131

It is short phase of cell cycle . during Mitotic phase, cell undergoes division to produce daughter cells.

Question: 22

State cytokinesis.

Answer: 22

22-131

Cytokinesis the division of cytoplasm is called cytokinesis

Question: 23

What is kinetochore?

Answer: 23

23-131

Each chromosome has kinetochore at centromer kinetochore is a complex protein structure that is the point where spindle fibers attach.

Question: 24

What is meant by tumors?

Answer: 24

24-131

Sometimes mutation occur in such genes and cells continue to divide it results in growth of abnormal cells called tumors.

Question: 25

Write significance of meiosis in term of variation in organisms ?

Answer: 25

25-131

The chromosomes pairs of each parent under go Crossing over during meiosis.So daughter cells i.e.gametes have genetic variation
When gametes fuse and form zygote, its genetic make up is different form both parent

Question: 26

What is benign tumors.

Answer: 26

26-131

Benign tumors as long as these tumors remain in their original location, they are called benign tumors.

Question: 27

What is S-phase in cell cycle ?

Answer: 27

27-131

In S-phase cell duplicated its chromosomes .As a result each chromosomes consist of two sister chromatids.

Question: 28

DEfine Mitosis. Give its one benefit.

Answer: 28

28-131

Mitosis is a type of cell division in which a cell divides into two daughter cells. Each with the same number of chromosomes as was present in parent cell. Benefit. Importance of mitosis is the maintenance of chromosome set i.e. each daughter cell receives chromosomes that are alike in composition and equal in number to the chromosomes of parent cell.

Question: 29

How is metaphase plate formed ?

Answer: 29

29-131

Chromosomes arrange themselves at the equator region in metaphase of karyokinesis division of mitosis and hence forms metaphase plate

Question: 30

Define Reproduction.

Answer: 30

30-131

Reproduction: Reproduction is a biological process by which living things produce the individuals of the same species, i.e. the next generation of species. The most basic characteristics of life is "reproduction " reproduction occurs at different levels of organization .Parts of cell such as chromosomes produce new chromosomes, cells produce new cells this all involves in reproduction..

Question: 31

Define malignant?

Answer: 31

31-131

They include other tissues they are called malignant tumors and their cells are called comers cells.

Question: 32

How cytokinesis occur ?

Answer: 32

32-131

cytokinesis in plant cell occurs differently. Vesicles derived from the Golgi apparatus membrane-bonded disc called the cell plate or phragmoplates

Question: 33

What is difference between inter phase and inter phases II.

Answer: 33

33-131

Inter phase: Inter phase has 8 phase to duplicate chromosomes.

Question: 34

Give name of phases of mitosis ?

Answer: 34

34-131

Karyokinesis
Cytokinesis

Question: 35

When and who discoverd the process of mitosis ?

Answer: 35

35-131

In 1880's , a germen biologist walther Flemming observed that in a dividing cell nucleus passes through a series of change which he called mitosis

Question: 36

What is malignant tumor ?

Answer: 36

36-131

Malignant tumor can send the cancer cell to other prats in the body where new tumors may form. This phenomenon is called metastasis

Question: 37

Define Mitotic spindle ?

Answer: 37

37-131

In prophase centrosomes give rise microtubules by joining tubulin proteins present in cytoplasm

Question: 38

What is mitosis?

Answer: 38

38-131

Mitosis is the type of cells division in which a cell divides into two daughter cells, each with the same number of chromosomes as were presents in parent cell

Question: 39

Define Chromatin ?

Answer: 39

39-131

Chromatin is the hereditary material in the nucleus in the form of loose, thread like form. it is present normally when cell is not diving

Question: 40

What is the role of mitosis in development and growth ?

Answer: 40

40-131

Importance of mitosis is the maintenan of chromosornal set. The number of cell within an organisms increased by mitosis.

Question: 41

Define phargmoplast?

Answer: 41

41-131

The pharmoplast is a plant cells specific structure that forms during late cytokinesisIt serves as a scaffold for cell plate assembly and subsequent

Question: 42

What is G2 phase ?

Answer: 42

42-131

in G2 phase cell prepare protein that are essential for mitosis, mainly for the production of spindle fibers.

Question: 43

Write type of Reproduction ?

Answer: 43

43-131

Asexual Reproduction
Sexual Reproduction

Question: 44

Differentiate diploid and haploid cell ?

Answer: 44

44-131

Diploid (2n) means the cell in which chromosomes are in pairs
While haploid (n) means the cells with half number of chromosomes i.e.chromosomes are not in the form of pairs

Question: 45

What is meant by Phragmoplast ?

Answer: 45

45-131

Cytokinesis in plant cells occur differently. Vesicles derived from the Golgi apparatus move to the middle of cells and fuse to form a membranous disk this disk is known as phragmoplast

Question: 46

Define alternation of generation ?

Answer: 46

46-131

Plants show alternation of generation in their life cycle.
diploid sporophyte generation undergoes meiosis and form haploid spores which grow to produce haploid gemetophyte generation

Question: 47

What is tumors ?

Answer: 47

47-131

Tumors are abnormal cell which grow due to abnormal division of cell .

Question: 48

What is Disjunction ?

Answer: 48

48-131

During anaphase I chromosomes separate and go to opposite poles while during anaphase II sister chromosomes separate.

Question: 49

Describe Asexual reproduction in hydra :

Asexual reproduction in hydra takes place through budding.

Answer: 49

49-131

During Budding, Cell on the surface of body of hydra undergoes mitosis and a cluster of cell are formed called bud

Question: 50

Differentiate between interphase and mitotic phase

Answer: 50

50-131

Interphase: Interphase is the phase between two consecutive mitotic phase During interphase metabolic activities of cell rises Interphase is further divided into three steps

G1-phase , S-phase, G2phase

Question: 51

How are spindle fibers formed during prophase of mitosis?

Answer: 51

51-131

In prophase, Centrosomes give rise to microtubules by joining tubulin proteins present in cytoplasm the microtubles thus formed are called spindle fibers

Question: 52

Define Metastasis

Answer: 52

52-131

Such tumor scanssend cancer cells to other plants in body where new tumor may form This phenomenon is called metastasis.

Question: 53

What is regeneration ?

Answer: 53

53-131

Some organisms can be regenerate part of their bodies the production of new cell is achieved by mitosis like sea star regenerates its lost part by the regeneration

Question: 54

Define cell replacement ?

Answer: 54

54-131

New cell are formed by the mitosis and so are exact copies of the cell being replaced.Red blood cells have short life span and new red blood cells are formed by mitosis

Question: 55

What is cell cycle?

Answer: 55

55-131

The Cell cycle is the series of events from the time a cell is produced untilit completes mitosis and produce new cell.

Question: 56

What is difference phase

Answer: 56

56-131

The process of mitosis is complex and highly regulaed. there are two major phases the division of nucleus known karyokinesis and the division of cytokinesis.

Question: 57

What is meant by Cleavages furrow

Answer: 57

57-131

In animal cells cytokinesis occurs by process known as cleavage A cleavage furrow develops where the metaphase plate used to be The furrow deepens and eventually pinches the parent cell into two daughter cells

Question: 58

Define S-shape ?

Answer: 58

58-131

In S-shape cell duplicated its chromosomes.As a result each chromosome consists of two sister chromatids

Question: 59

Define Chiasmata ?

Answer: 59

59-131

Chiasmata are formed during the prophase-I of meiosis-I these are the point attachment between non-sister chromatids of homologous chromosomes

Question: 60

Define Synapsis ?

Answer: 60

60-131

During prophase 1 of Meiosis 1 homologous chromosomes line up with each other and form pairs by process called Synapsis.

Question: 61

Differentiate between somatic cell germ cell ?

Answer: 61

61-131

Somatic Cell:

Somatic cell are those which form the body of organisms.
Somatic cell undergo mitosis

Question: 62

When and who discoverd crossing over in drosophilla melanogaster ?

Answer: 62

62-131

In 1911 the american geneticist Thomas Hunt Morgan discoverd the phenomenon of crossing over in fruit by drosophilla melanogaster

Question: 63

What changes are placed in telophase I during meiosis?

Answer: 63

63-131

In telophase I Chromosomes arrive at the pole.Each pole now has half the number of chromosomes But each chromosomes still consists of two chromatids

Question: 64

Plant do not make their gametes by meiosis.Why ?

Answer: 64

64-131

Plant do not make their gametes by meiosis because plant gametes are already haploid (n)

Question: 65

Explain S-phase in cell cycle

Answer: 65

65-131

In S-phase, cell duplicates its chromosomes As a result each chromosome consists of two sister chromatids

Question: 66

Define Meiosis ? Which biologist discover meiosis ?

Answer: 66

66-131

Meiosis:Meiosis is a process in which a Eukaryotic diploid cell divided and forms four haploid

Discover:Meiosis was discovered and described for the first time in 1816 by a German biologist Oscar Hertwig

Question: 67

Define Regeneration?

Answer: 67

67-131

Some organisms can regenerate points of their bodies the production of new cell is achieved by mitosis, For example sea star regenerates its last arm through mitosis

Question: 68

Define Crossing Over ?

Answer: 68

68-131

The exchange of segments between the non-sister chromatids of homologous chromosomes during meiosis

Question: 69

Define mitosis

Answer: 69

69-131

Mitosis is the type of cells division in which a cell divides into two daughter cells, each with the same number of chromosomes as were present in parent cell

Question: 70

Define Meiosis Which biologist discover Meiosis

Answer: 70

70-131

Meiosis: Meiosis is a process in which a Eukaryotic diploid cell divide and form four haploid cells

Question: 71

Why are tumors dangerous for human body ?

Answer: 71

71-131

Tumors become dangerous for human body when they attack on others tissues of the body Such tumors are called malignant or cancerous tumors

Question: 72

Define Homologous chromosomes:

Answer: 72

72-131

A pair of chromosomes having the same size and shape and carrying alleles for the same traits

Question: 73

What is interphase?

Answer: 73

73-131

interphase is the time when a cell's metabolic activity as very high as it perform its various function

Question: 74

Define Apoptosis:

Answer: 74

74-131

Apoptosis :

Apoptosisis one of the main types of programmed cell death. cell shrinks and become rounded due to the breakdown of cytoskeletion by enzymes

Question: 75

Define Mitosis Which biologist discover Meossis

Answer: 75

75-131

A type of cell division which produce daughter cell identical to the parents

Question: 76

What is Anaphase?

Answer: 76

76-131

When a rinetochorespindle fiber connects with the rinetochre of chromosomes. It starts to pull toward the originatingcentrosomes.

Question: 77

Write two source of occurrence of necrosis ?

Answer: 77

77-131

Injury
Infection
Cancer

Question: 78

Write a significance of meosis?

Answer: 78

78-131

Important of meiosis the significant of meiosis for reproduction and inheritancewas described in 1890 by german biologist August weirman. He pointed out that meiosis was necessarynot only to maintain the number of chromosome in the next generation but also to produce in next generation.

Question: 79

What are the effects of errors in meiosis

Answer: 79

79-131

Disjunction: During anaphase chromosomes separate and go to opposite poles while during anaphase sister chromosomes separte It is called disjunction

Question: 80

What is necrosis ?

Answer: 80

80-131

The accidental death of cell and tissues is called necrosis.

Question: 81

How cytokinesis is different in plant cells as

Answer: 81

81-131

Cytokinesis in plants: Cytokinesis in plant cells occurs differently Vesicles derived from the Golgi aparatus move to the middle of the cell and fuse to form a phragmoplast The plate grows outward and more vesicle fuse with it Finally the membranes of the cell plate fuse with the plasma membrane and its contents join the parental cell wall The result is two daughter cells, each bounded by its own plasma membrane and cell wall

Question: 82

Define karyokinisi?

Answer: 82

82-131

Karyokinsis the division of nucleus is further divided into few phase parophasemetaphorsamorphousand telopase

Question: 83

What id budding?

Answer: 83

83-131

A types of asexual reproduction in which a bud develops as a small outgrowth ofparent's body and forms the new individual.

Question: 84

Define alternation of generations

Answer: 84

84-131

Alternation of Generations: Plants show alternation generation in their life cycle Diploid sporophyte generation undergoes Meiosis and Diploid sporophyte generation

Gametophyte generation under go mitosis to form haploid gametes which unite to produce diploid zygote Zygote grows through mitosis into diploid sporophyte generation

Question: 85

Define cytokinesis?

Answer: 85

85-131

The division of the cytoplasium after nuclear division

Question: 86

Define Telophase?

Answer: 86

86-131

Telophase is a reversal of praphase. Anew nuclear encelop forms around each other ser of seperaed chromosomes

Question: 87

What is Meiosis

Answer: 87

87-131

Meiosis is the process by which one diploid eukaryotic cell divides to generate four haploid daughter cells

Question: 88

What is tumor and what are benign and malignant?

Answer: 88

88-131

sometimesamutation occurs in such genes and cells continued to divide. It results in grouth of abnormal cells called tumors. they invade other tissues they are called malignant.

Question: 89

What is metaphase?

Answer: 89

89-131

When spindle fibers have grown to sufficientlength some spindlefibers known as fibrilsKinetochore attach with Kinetochare of chromosome

Question: 90

Name two phases of cell cycle. Which phase in divide into three phases

Answer: 90

90-131

Phases of cell cycle: Interphase, Mitotic phase or m-phase

Question: 91

Write difference between mitosis and meiosis

Answer: 91

91-131

Meiosis: Meiosis was discovered and described for the first time in 1816 by a German biologist Oscar HartwigIn this process of cell division One parent cell produce four daughter cellsDue to meiosis each daughter cell have half number of chromosomes as present in parent cellMeiosis takes place is germ cellsCrossing over and mutation takes place in this process

Question: 92

Define synapsis?

Answer: 92

92-131

A junction between a neuron and another cell transmits nerve impulse from one neuron to the next neuron of to effectorscell

Question: 93

Give the name of phases of mitosis

Answer: 93

93-131

There are two major phases of mitosis

Question: 94

Define spindle?

Answer: 94

94-131

The microtubulesthus formed are called spindle fibres

Question: 95

Plant do not make their gametes by meiosis

Answer: 95

95-131

Plants do not make their gametes by meiosis because plants gametes are already haploid

Question: 96

Write types of Reproduction

Answer: 96

96-131

Asexual Reproduction

sexual Reproduction

Question: 97

What is necrosis

Answer: 97

97-131

Necrosis: The accidental death of cells and tissues is called Necrosis

Question: 98

Define Mitosis and Mitotic Spindle

Answer: 98

98-131

Mitosis: Mitosis is the type of cells division in which a cell divides into two daughter cells each with the same number of chromosomes as were present in parent cell

Question: 99

How is metaphase plate formed

Answer: 99

99-131

Chromosomes arrange themselves at the equator region in metaphase of Karyokinetic division of mitosis and hence form metaphase plate

Question: 100

What is kinetochore

Answer: 100

100-131

Each chromosome has kinetochore at centromere Kinetochore is a complex protein structure that is the point where spindle fibers attach

Question: 101

What is the importance of Apoptosis

Answer: 101

101-131

Apoptosis can occur when a cell is damaged or undergoes stress conditions Apoptosis removes the damaged cell preventing it from getting further nutrients or to prevent the spread of infections

Apoptosis also gives advantages during development For a example during the formation of fingers the cells between them undergo apoptosis and the digits separates

Question: 102

Explain briefly how asexual reproduction occurs in Hydra

Answer: 102

102-131

Asexual Reproduction in Hydra: Asexual reproduction in Hydra takes place through Budding

During Budding Cells on the surface of body of Hydra undergoes mitosis and a cluster of cells are formed called Bud

Mitosis continues in cells of bud and it increase in size to form a new Hydra

Question: 103

When and who discovered the process of Mitosis

Answer: 103

103-131

In 1880 a Germen biologist Walther Fleming observed that in a dividing cell nucleus passes through a series of changes which he called mitosis

Question: 104

What is the role of Lysosome in necrosis

Answer: 104

104-131

During necrosis there is a release of special enzymes from lysosomes Lysosomal enzymes break cellular components and may also be released outside cell to break surrounding cells Cells that die by necrosis may also release harmful chemicals that damage other cells

Question: 105

When chiasmata are formed

Answer: 105

105-131

Chiasmata are formed during the Prophase of meiosis chromatids of homologous chromosomes

Question: 106

What is meant by G0 Phase

Answer: 106

106-131

In multicellular eukaryotes, cells enter g0 phase from G1 and stop dividing Some cells remain in G0 phase semi-permeable e.g some cells of liver and kidney Many cells do not enter Go and continue to divide throughout an organisms life, e.g epithelial cells

Question: 107

Differentiate between chromatin and chromosome

Answer: 107

107-131

Chromatin: Chromatin is the hereditary material in nucleus in the form of loose, thread like form It is present normally when cellis not dividing

Question: 108

Differentiate between S phase and G2 phase

Answer: 108

108-131

The difference between S-phase and G2 phase is given below

S-phase In s-phase cell duplicates its chromosomes As a its chromosomes As a result each chromosome consists of two sister chromatids

Question: 109

What is meant by Metastasis

Answer: 109

109-131

Malignant tumors can send the cancer cells to other parts in the body where new tumors may form The phenomenon is called metastasis means spreading of diseases

Question: 110

Define cell cycle

Answer: 110

110-131

Anabolism Anabolism include all those biochemical reaction in which larger molecules are formed from smaller molecules Energy is used in anabolism

Question: 111

What are benign and Malignant Tumors

Answer: 111

111-131

Benign tumor: If tumors remain in their original location for a log time they are called benign tumors

Question: 112

Write two significances of Mitosis

Answer: 112

112-131

Cell replacement: New cells are formed by mitosis and so are exact copies of the cells have short life span about months and new red blood cells are formed by mitosis

Question: 113

What is the role of mitosis in development and growth

Answer: 113

113-131

Importance of mitosis is the maintenance of chromosomal set The number of cells within an organism increased by mitosis This is the basis of the development of cellular body from a single cell like zygote and also the basic of the growth of multicellular body

Question: 114

What is phragmoplast

Answer: 114

114-131

Cytokinesis in plant cells occurs differently Vesicles derived from the Golgi apparatus move to the middle of cell and fuse to form a membranous disk This disk is known as cell plate or phragmoplast

Question: 115

Write significance of Meiosis in term of variation in organisms

Answer: 115

115-131

The chromosomes pairs of each parent undergo crossing over during meiosis So daughter cells i.e gametes have genetic variations
When gametes fuse and form zygote, its genetic make up is different from both parents Thus meiosis allows a species to bring variations in the next generations

Beneficial variations help organisms to adapt to the change in enviroment

Question: 116

What is Regeneration

Answer: 116

116-131

Regeneration: Some organisms can regenerate parts of their bodies The production of new cells is achieved by mitosis like sea star regenerates its lost part by regeneration

Question: 117

What changes are placed in telophase I during meiosis

Answer: 117

117-131

In telophase I Chromosomes arrive at the poles Each pole now has half the number of chromosomes but each chromosome still consists of two chromatids The spindle network disappears and nuclear envelope is formed around each haploid set The chromosomes uncoil back into chromatin

Question: 118

What is Mitotic Spindle

Answer: 118

118-131

In prophase, centrosomes give rise to microtubules by joining tubulin proteins present in cytoplasm The microtubules thus formed are called spindle fibers Complete set of spindle fibers is known as mitotic spindle

Question: 119

Define somatic cells

Answer: 119

119-131

Somatic cells are those which form the body of organismsSomatic cells undergo mitosis

Question: 120

Name the phases of Karyokinesis

Answer: 120

120-131

Prophase, Metaphase, Anaphase, Telophase

Question: 121

Define Crossing Over

Answer: 121

121-131

The exchange of segments between the non-sister chromatids of homologues chromosomes during meiosis

Question: 122

Differentiate diploid and Haploid cell

Answer: 122

122-131

Diploid means the cells in which chromosomes are in pairs homologous pairswhile haploid means the cells with half number of chromosomes i.e. chromosomes are not in the form of pairs

Question: 123

Define Synapsis

Answer: 123

123-131

During prophase of Meiosis homologous chromosomes line up with each other and form Paris by a process called Synapsis

Question: 124

Why are tumors dangerous for human body

Answer: 124

124-131

Tumors become dangerous for human body when they attack on other tissues of the body Such tumors are called malignant or cancerous tumors Such tumors send cancerous cells to others parts of the body where they form new tumors This process of spreading of diseaase is called Metastasis

Question: 125

Define Apoptosis

Answer: 125

125-131

Apoptosis is one of the main types of programmed cel death It occur when cell damaged or undergoes stress conditions

Question: 126

What are tumors

Answer: 126

126-131

Tumors are abnormal cells which grow due to abnormal division of cells

Question: 127

Write two sources of occurrence of necrosis

Answer: 127

127-131

Injury, Infection, Cancer

Question: 128

Define Belebs

Answer: 128

128-131

During apoptosis cell shrinks and becomes rounded due to the breakdown of cytoskeleton by enzymes Its chromatin undergoes condensation and nuclear envelope breaks in this way nucleus spread in the form of several discern chromatin bodies cell membrane makes irregular buds known as beds Bled's break off from the cell and are now called apoptotic bodies which are then phagocytosed by other cells

Question: 129

When and who discovered crossing over in Drosophila Melanogaster

Answer: 129

129-131

In 1911 the American geneticist Thomas Hunt Morgan discovered the phenomenon of crossing over in fruit fly Drosophila melanogaster

Question: 130

Write down function of chiasmata in crossing over process

Answer: 130

130-131

Chiasmata are point of attachments between non-sister chromatids of homologous chromosomes It is the first step for irregular exhange of chromosomal segments

Question: 131

Write the difference between apoptosis and necrosis

Answer: 131

131-131

Difference between apoptosis and necrosis is given below

Apoptosis: Apoptosis is one of the main types of programmed cell death

Apoptosis can occur when a cell is damaged or undergone stress conditions

Biology Chapters

9th Class Chapter 5 Biology Short Questions

0

Perparation Level