XI: Chapter 8- Cell the unit of life Flashcards Preview

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Flashcards in XI: Chapter 8- Cell the unit of life Deck (180)
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1
Q

Who is the father of cytology?

A

Robert Hooke

2
Q

Who is the father of microscopy?

A

A.V. Leeuwenhook

3
Q

Who coined the term cell?

A

Robert Hooke

4
Q

Who discovered the first living cell?

A

A.V. Leeuwenhook

5
Q

Which botanist contributed to the cell theory?

A

M. Schledein

6
Q

Which zoologist contributed to the cell theory?

A

T. Schwann

7
Q

Who proposed the cell lineage theory?

A

Rudolf Virchow

8
Q

Who discovered the nucleus?

A

Robert Brown

9
Q

Which is the largest plant cell?

A

Acetabularia

10
Q

Which is the largest animal cell?

A

Ostrich egg cell

11
Q

Sterols are present in which prokaryote?

A

Mycoplasma

12
Q

What is the difference between the structure of pili and fimbriae?

A

Pili- hollow filament

Fimbrae- solid filament

13
Q

What is the glycocalyx made of?

A

Oligosaccharides

14
Q

What is the difference between the golgi bodies of animals and plants?

A

A single large golgisome is present in animal cells near the nucleus while dictyosomes are minute, many and scattered.

15
Q

Which cells have more mitochondria- animal cells or plant cells?

A

Animal cells

16
Q

Are centrosomes present in plants?

A

No

17
Q

What is deutoplasm?

A

Non living inclusion bodies in a eukaryotic cell

18
Q

What is hyaloplasm?

A

Cytoplasm-organelles-deutoplasm

19
Q

In which plant cells are cell walls absent?

A

In gametes of plants

20
Q

What is the constitution of plant cell wall?

A

Plant cell wall is made of cellulose macrofibrils embedded in matrix of hemicellulose, pectin and lignin.

21
Q

What is the constitution of algal cell wall?

A

Cellulose macrofibrils embedded in matrix of hemicellulose, pectin, galactans and mannans

22
Q

What is the constitution of fungal cell wall?

A

Chitin and cellulose macrofibrils embedded in matrix of hemicellulose and pectin

23
Q

What is the precursor of middle lamella, and what is the middle lamella a precursor of?

A

Cell plate is the prescursor of middle lamella while middle lamella is the precursor of cell wall.

24
Q

What makes fruits soft on ripening?

A

Dissolution of middle lamella (pectinase enzyme)

25
Q

At which angle are the cellulose microfibrils situated to each other in the cell wall?

A

120`

26
Q

What makes the primary cell wall more flexible than the secondary cell wall?

A

Primary cell wall- more of pectin

Secondary cell wall- more of lignin

27
Q

Which cell wall is deposited uniformly?

A

Primary cell wall

28
Q

What is the tertiary cell wall made of?

A

Xylans

29
Q

What are desmotubules of plasmodesmata made of?

A

Endoplasmic reticulum

30
Q

What is the tonoplast in a plant cell?

A

The living semi-permeable single membrane of a vacuole

31
Q

Does the transport of material across the tonoplast occur against or along the concentration gradient?

A

Against

32
Q

Where are anthocyanins stored in a plant cell?

A

Vacuole

33
Q

Who discovered the plasma membrane?

A

Schwann

34
Q

What is the composition of cell membrane?

A

40% lipids
52% proteins
8% carbohydrates

35
Q

Who proposed the sandwhich theory of plasma membrane?

A

Danielli and Davson

36
Q

What is the width of the plasma membrane according to the sandwhich theory?

A

20 Å Protein layer
35 Å lipid bilayer
20 Å Protein layer

37
Q

Which is the most common phospholipid found in cells?

A

Lecithin

38
Q

Who proposed the fluid mosaic model?

A

Singer and Nicolson

39
Q

What is the difference in the amount of cholesterol find in plant and animal cell membranes?

A

Plant cell membranes have less cholesterol or sometimes no cholesterol as compared to animal cell membranes.

40
Q

What is the function of cholesterol in plasma membrane?

A

Cholesterol provides stability to the cell membrane.

41
Q

Lateral movements happen between which layers of cell membrane?

A

Same layers

42
Q

What regulates the permeability of cell membrane?

A

Calcium ions

43
Q

Sodium potassium pump is the example of which type of active transport?

A

Direct active transport

44
Q

SGLT (intestinal mucosa sodium glucose transport) is the example of which type of active transport?

A

Indirect active transport

45
Q

GLUT is an example of which type of transport?

A

Facilated transport

46
Q

What type of membrane binds the endoplasmic reticulum?

A

Single membrane

47
Q

Who discovered the endoplasmic reticulum?

A

Porter

48
Q

In which cells is endoplasmic reticulum poorly developed?

A

In rapidly dividing cells- sperms, ovum and RBCs

49
Q

What are the structural forms of ER?

A

Vesicles, tubules and cisternae

50
Q

How is the larger unit of ribosome attached to RER?

A

With glycoproteins= ribophorin I and II

51
Q

Which cell organelle is responsible for detoxification of toxins in liver?

A

SER

52
Q

Which cell organelle forms enzyme precursors of lysosomes to be made by golgi bodies?

A

RER

53
Q

How is SER able to detoxify toxins in liver?

A

Because of cytochrome 450

54
Q

In which cell organelle are calcium ions store in muscle cells?

A

SER (sarcoplasmic reticulum)

55
Q

Which organelle forms the cell endoskeleton?

A

Endoplasmic reticulum

56
Q

What are the cytoplasmic bridges between two adjacent plant cells?

A

Plasmodesmata

57
Q

Which organelle helps in reformation of nuclear membrane at the end of cell division?

A

ER

58
Q

What is the functional unit of golgi body?

A

Cisternae

59
Q

How many golgiosomes are present in animal cells?

A

4 to 8

60
Q

In which human cells are golgi bodies absent?

A

Mature RBCs

61
Q

Which is the convex face of golgisome?

A

Cis face/forming face

62
Q

Which is the concave face of golgisome?

A

Trans face/maturing face

63
Q

Which cell organelle synthesises carbohydrates?

A

Golgi body

64
Q

Which cell organelle synthesises glycoproteins and glycolipids?

A

Golgi body

65
Q

Which enzyme helps in glycosylation of proteins and lipids in golgibodies?

A

Glycosyl transferase enzyme

66
Q

Which organelle is responsible for the formation of cell plate?

A

Golgi body

67
Q

Which organelle is responsible for the repairing of cell wall?

A

Golgi body

68
Q

Which organelle is responsible for the formation of yolk in egg?

A

Golgi body

69
Q

Who discovered lysosomes?

A

Christian-de-duve

70
Q

What is the pH of lysosomes?

A

4 to 5

71
Q

What is the marker enzyme for lysosome?

A

Acid phosphatase

72
Q

Lysosomes are absent in which human cell?

A

RBCs

73
Q

Lysosomes are found in which plant cell?

A

Maize root, tobacco endosperm

74
Q

How are primary lysosomes formed?

A

Primary lysosomes form from golgi bodies.

75
Q

WHat do primary lysosomes contain?

A

Inactive enzymes

76
Q

How are secondary lysosomes formed?

A

Primary lysosomes + food vacuole

77
Q

What do secondary lysosomes contain?

A

Active enzymes

78
Q

What are tertiary lysosomes?

A

Contain undigested waste

79
Q

What is the function of an autophagosome?

A

Recycling of old worn out cell organelles

80
Q

How are lysosomes related to Tay-Sachs and Gaucher’s disease?

A

These diseases occur because of the accumulation of tertiary lysosomes

81
Q

What make lysosomes rupture?

A

Membrane labilizers

82
Q

Give examples of membrane labilizers.

A

Vit A, vit B, sex hormones, bile salts etc

83
Q

Give examples of membrane stabilizers.

A

Cortisol, cholesterol, heparin

84
Q

Can a lysosome rupture on its own?

A

No

85
Q

What kind of membrane surrounds the microbodies in a cell?

A

Single membrane

86
Q

Which microbody is found in plant cells only?

A

Sphaerosome

87
Q

What is the function of sphaerosome?

A

Lipid storage

88
Q

Which microbody is known as plant lysosome?

A

Sphaerosome

89
Q

Where are glyoxisomes found?

A

Seeds of plants and fungi

90
Q

What is the function of glyoxisome?

A

Conversion of oil/fat to sugar/carbohydrate

91
Q

Which is the main class of enzymes found in peroxisomes of plants?

A

Glycolate oxidase

92
Q

Which is the main class of enzymes found in peroxisomes of animals?

A

Purine/urate oxidase

93
Q

Can double membrane bound organelles stay alive outside a cell?

A

Yes

94
Q

Which organelles are known as cell within a cell?

A

Double membrane bound organelles

95
Q

Which is the largest organelle of an animal cell?

A

Mitochondria

96
Q

Aquaporins are present on which membrane of mitochondria?

A

Outer membrane

97
Q

Where is succinic dehydrogenase enzyme located in a mitochondria?

A

Inner membrane

98
Q

Where are the enzymes of Kreb’s cycle present in a mitochondria?

A

In the matrix

99
Q

Where does the β oxidation of fatty acids occur in a cell?

A

Mitochondria

100
Q

Which is the largest organelle of a plant cell?

A

Plastids

101
Q

Which leucoplast stores starch?

A

Amyloplast

102
Q

Which leucoplast stores proteins?

A

Aleuroplast

103
Q

Which leucoplast stores fats?

A

Elaioplast

104
Q

What are known as Palade particles?

A

Ribosomes

105
Q

What is known as organelle within organelle?

A

Ribosomes

106
Q

Which is the smallest cell organelle?

A

Ribosome

107
Q

At what concentration of Mg2+ ions, the dimer of ribosomes is formed?

A

0.001 M

108
Q

How many types of proteins are found in prokaryotic ribosomes?

A

55 types of proteins

109
Q

Which RNA form the 50s ribosomal unit?

A

23s rRNA, 5s rRNA

110
Q

Which RNA forms the 30s ribosomal unit?

A

16s rRNA

111
Q

How many types of proteins form the eukaryotic ribosome?

A

73 types of proteins

112
Q

Which RNA form the 60s ribosomal unit?

A

28s rRNA, 5s rRNA, 5.8s rRNA

113
Q

Which RNA form the 40s ribosomal unit

A

18s rRNA

114
Q

Which rRNA are ribozymes?

A

23s rRNA and 28s rRNA

115
Q

Which RNA is extranuclear in origin?

A

5s rRNA

116
Q

Which cytoskeletal fibres are thin, solid and contractile?

A

Microfilaments

117
Q

Which protein forms microfilaments?

A

Actin proteins

118
Q

Which cytoskeletal fibre is responsible for pseudopodia formation and cytolpasmic streaming?

A

Microfilaments

119
Q

Which cytoskeletal fibre is strong, solid and contractile?

A

Intermediate protein fibre

120
Q

Which protein forms the intermediate protein fibre?

A

Keratin

121
Q

Which cytoskeletal fibres are present in desmosomes?

A

Intermediate protein fibres

122
Q

Which cytoskeletal fibres form the nuclear basket?

A

Intermediate protein fibres

123
Q

Which cytoskeletal fibre is hollow, broad and non contractile?

A

Microtubules

124
Q

Which protein forms the microtubules?

A

1 α-tubulin + 1 β-tubulin

125
Q

How many protofilaments come together to form a singlet microtubule?

A

13 protofilaments

126
Q

What is centrosphere?

A

It is the amorphous cytoplasm surrounding centrioles

127
Q

Where are centrosomes located?

A

Near the nuclear membrane

128
Q

Which organelle forms the basal body?

A

Centrosome

129
Q

What microtubular arrangement is present in centrioles?

A

9+0

130
Q

Oocytes lack which cell organelle?

A

Centriole

131
Q

What do the linker proteins link in a centriole?

A

Adjacently placed A and C microtubules

132
Q

What is the core of cilia/flagella of eukaryotes called?

A

Axoneme

133
Q

What is the difference between the peripheral microtubules of centriole and flagella?

A

Centriole- peripheral triplets

Flagella- peripheral doublets

134
Q

What links the adjacent peripheral microtubule doublets in flagella/cilia?

A

Nexin protein

135
Q

What are the radial spokes of cilia/flagella made of?

A

Nexin protein

136
Q

What is the central sheath of axoneme made of in cilia/flagella?

A

Dyenin protein

137
Q

What are the inner and outer arms of peripheral microtubules made of in cilia/flagella?

A

Dyenin protein

138
Q

What acts as ATPase enzyme in cilia/flagella?

A

Dyenin protein

139
Q

What is the pH of nucleoplasm?

A

7.2 to 7.5

140
Q

What makes the nucleoplasm basic in nature?

A

Presence of large amounts of nucleosides

141
Q

How many histone proteins are present in a nucleosome?

A

5 types of histone proteins

142
Q

Which histone protein is called the linker protein?

A

H1

143
Q

Which is more condensed- euchromatin or heterochromatin?

A

Heterochromatin

144
Q

Which gets lightly stained- euchromatin or heterochromatin?

A

Euchromatin

145
Q

What is the shape of heterochromatin?

A

Solenoid

146
Q

Which type of chromatin is present in nucleolus?

A

Heterochromatin

147
Q

What is the ribosomal factory of cell?

A

Nucleolus

148
Q

Which animal has maximum number of chromosomes?

A

aulacanthus

149
Q

Which plant has maximum number of chromosomes?

A

Ophioglossum

150
Q

Which animal has minimum number of chromosome?

A

Ascaris

151
Q

How many chromatonemata are present in a chromosome?

A

2

152
Q

What is NOR?

A

Nuclear organizing region, aka secondary centromere

153
Q

In which chromosomes is primary constriction located?

A

All chromosomes

154
Q

Which nitrogenous bases are the chromosomal constrictions rich in?

A

Adenine and thymine

155
Q

What is a v-shaped chromosome?

A

Metacentric chromosome

156
Q

What is a L-shaped chromosome?

A

Sub-metacentric chromosome

157
Q

What is a J-shaped chromosome?

A

Acrocentric chromosome

158
Q

What is an i- shaped chromosome?

A

Telocentric chromosome

159
Q

Polytene chromosomes are found in

A

Salivary glands of insects

160
Q

WHat is the function of polytene chromosomes?

A

Synthesise proteins required for metamorphosis

161
Q

Who discovered polytene chromosome?

A

Balbiani

162
Q

Lamp brush chromosomes are found in

A

Oocytes of insects/amphibians

163
Q

Which is bigger- giant chromosome or lampbrush chromosome?

A

Lamp-brush chromosome

164
Q

What is the function of lamp-brush chromosomes?

A

Contain yolk producing genes

165
Q

Which multiply faster- prokaryotes or eukaryotes?

A

Prokaryotes

166
Q

Mesosomes occur in the form of

A

Vesicles, tubules and lamellae

167
Q

Inclusion bodies in prokaryotes are bound to

A

They are free

168
Q

Which part of cell envelope of plant cell helps in cell to cell recognition?

A

Cell wall

169
Q

Can the primary cell wall grow?

A

Yes

170
Q

What happens to the primary cell wall as it matures?

A

It diminishes

171
Q

Are vacuoles a part of endomembrane system?

A

Yes

172
Q

Where is the luminal compartment of cells?

A

Inside ER

173
Q

Which ER is continuous with the nuclear membrane?

A

RER

174
Q

The cis and trans face of golgi bodies are similar. True or false?

A

False

175
Q

How do mitochondria divide?

A

Fission

176
Q

How many chloroplasts are present in a mesophyll cell?

A

20 to 40

177
Q

Which tubules connect grana?

A

Stroma lamellae

178
Q

What does the ‘Svedberg’ unit signify?

A

Density and size

179
Q

Which dyes stain the chromatin?

A

Basic dyes

180
Q

Who coined the term ‘chromatin’?

A

Flemming

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