Multiple Choice QuestionsMembrane -bound organelles are absent in
Saccharomyces
Streptococcus
Chlamydomonas
Chlamydomonas
Which one of the following has its own DNA?
Mitochondria
Dictyosome
Lysosome
Lysosome
Select the correct statements out of the four (1-4) given below about lac operon.
Glucose or galactose may bind with the repressor and inactivate it
In the absence of lactose, the repressor binds with the operator region
The z- gene codes for permease
The z- gene codes for permease
The main arean of various types of activities of a cell is
Plasma membrane
mitochondrion
cytoplasm
cytoplasm
The plasma membrane consist mainly of
phospholipids embedded in a protein bilayer
Proteins embedded in a phospholipid bilayer
proteins embedded in a polymer of glucose molecules
proteins embedded in a polymer of glucose molecules
B.
Proteins embedded in a phospholipid bilayer
According to fluid mosaic model given by Singer and Nicholson (1972), Plasma membrane consists of a continuous bilayer of phospholipid molecules, in which globular proteins are embedded. This arrangement corresponds to icebergs (proteins) floating in a sea of phospholipids. Proteins stay in the membrane because they have regions of hydrophobic amino acids which interact with fatty acid tails to exclude water. Rest of the molecules is hydrophilic, which faces into or outward, both of which are the aqueous environment.
If for some reason the parietal cells of the gut epithelium become partially non-functional, what is likely to happen?
The pancreatic enzymes and specially the trypsin and lipase will not work efficiently
The pH of stomach will fall abruptly
Steapsin will be more effective
Steapsin will be more effective
An elaborate network of filamentous proteinaceous structures present in the cytoplasm which helps in the maintenance of cell shape is called
thylakoid
endoplasmic reticulum
plasmalemma
plasmalemma
Identify the components labelled A, B, C and D in the diagram below from the list 1 to 8 given along with
1) Cristae of mitochondria
2) Inner membrane of mitochondria
3) Cytoplasm
4) Smooth endoplasmic reticulum
5) Rough endoplasmic reticulum
6) Mitochondrial matrix
7) cell vacuole
8) Nucleus
|
A |
B |
C |
D |
|
5 |
4 |
8 |
3 |
|
A |
B |
C |
D |
|
1 |
4 |
8 |
6 |
|
A |
B |
C |
D |
|
6 |
5 |
4 |
7 |
|
A |
B |
C |
D |
|
6 |
5 |
4 |
7 |
Middle lamella is mainly composed of
hemicellulose
muramic acid
calcium pectate
calcium pectate
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