The fluidity of membranes in a plant in cold weather may be maintained by
increasing the number of phospholipids with unsaturated hydrocarbon tails.
increasing the proportion of integral proteins.
increasing concentration of cholesterol in membrane.
increasing the number of phospholipids with saturated hydrocarbon tail.
Correct Answer :
A. increasing the number of phospholipids with unsaturated hydrocarbon tails.
The concept of membrane fluidity refer to the fact that both lipids and proteins may have considerable freedom of lateral movements within the bilayer. The fluidity of membranes in a plant in cold weather may be maintained by increasing the number of phospholipids with unsaturated hydrocarbon tails.
Related Questions
Identify the cell organelle given below. Which is an important site of formation of glyeoproteins & glycolipids
Rough endoplasmic reticulum
Smooth endoplasmic reticulum
Golgi body
mitochondria
The fluidity of membranes in a plant in cold weather may be maintained by
increasing the number of phospholipids with unsaturated hydrocarbon tails.
increasing the proportion of integral proteins.
increasing concentration of cholesterol in membrane.
increasing the number of phospholipids with saturated hydrocarbon tail.
In which of the following the cells are held together by a Ca-pectate layer?
Primary cell wall
Secondary cell wall
Middle lamella
Tertiary cell wall
Most of water, in mature plant cells occurs in
nucleus
cell wall
vacuoles
cytoplasm
The given figures show two types of cell. Which structures are common to both the cells?
Nucleus and cell wall
Nucleus and cytoplasm
Ribosomes and flagella
Ribosomes and cell wall
Axoneme with 9 + 2 microtubular arrangement occurs in
cilia
flagella
both (a) and (b)
centriole
Polysome is a chain of
oxysomes
sphaerosomes
ribosomes
dictyosomes
Microtubules, motor proteins, and actin filaments are all part of the
mechanism of photosynthesis that occurs in chloroplasts.
rough ER in prokaryotic cells.
cytoskeleton of eukaryotic cells.
process that moves small molecules across cell membranes.
9.A student was given cell samples (A and B) to identify parts which are highlighted. He observed the samples under the microscope and list down the function of the part of cell sample. The information collected by the student is listed in the table below, on the basis of which the student infers that the samples contain the organelles.
| Sample A | Sample B |
|---|---|
| Make energy available for cellular metabolism | Generates ATP and synthes izes s ugar |
| Absent in cell that carry oxygen throughout the body | Present in plant cell |
| Called the energy currency of cell | Source o f all the food energy |
Explain why the samples were belonged to eukaryotic cell and not prokaryotic cell? Because,
eukaryotic cell have membrane bound organelles.
eukaryotic cell have non - membrane bound organelles.
eukaryotic cell are smaller and multiply more rapidly than prokaryotic cells.
eukaryotic cell are larger and multiply more rapidly than prokaryotic cells.
Which of the following statements are correct?
Na+/K+ pump is an example of active transport.
In plant cells lipid like steroidal hormones are synthesized in SER.
In plant cells, the vacuoles can occupy up to 10% of the volume of the cell.
Chlorophyll and leucoplast are responsible for trapping light energy essential for photosynthesis.
Plastids are found in
all animal cells.
some animal cells.
all plant cells.
all plant cells and euglenoides.
Which one of the following combination is mismatched?
Glycocalyx May be capsule or slime layer
Pili Reproduction
Cell wall Protective, determines shape, prevents from bursting
Flagella, pili and fimbriae Surface structures of bacterial cell
Statement 1: Centrosomes and centrioles are related to each other.
Statement 2: Centrosome usually contains two cylindrical structures called centrioles.
Both statements -1 and statement - 2 are true and statement - 2 is the correct explanation of statement - 1.
Both statements -1 and statement - 2 are true but statement - 2 is not the correct explanation of statement - 1.
Statement -1 is true and statement - 2 is false.
Statement -1 is false and statement - 2 is true.
The lipid component of the membrane mainly consists of __________.
polysaccharides
phosphoglyceride
monosaccharaides
both (a) and (c)
Study the following statements on cilium or flagellum and answer the question.
- Cilium / Flagellum contains an outer ring of nine doublet microtubules surrounding two singlet microtubules.
- Cilia are smaller which work like oars, causing the movement of either the cells or surrounding fluid.
- Flagella are comparatively longer and responsible for cell movement.
- Cilium and flagellum are covered with plasma membrane.
Which of the above statements are correct?
(i) and (ii)
(i), (ii), (iii) and (iv)
(i) and (iv)
(ii) and (iii)
Which of the following will determines the shape of the cells and provides a strong structural support to prevent the bacterium from bursting or collapsing?
Plasmids
Cell wall
Mesosome
Cell membrane
Match column-I and column-II and select the correct answer
| Column-I | Column-II |
|---|---|
| A. Bacteria without walls | I. Lysosome |
| B. Small circular DNA | II. Mycoplasma cells |
| C. Flattened sacs in | III. Thylakoid a chloroplast |
| D. A vesicle in which | IV. Plasmid hydrolytic enzymes are stored |
A III; B IV; C II; D I
A II; B IV; C III; D I
A I; B II; C III; D IV
A IV; B III; C I ; D II
Both the membranes of mitochondrion are
structurally different but functionally similar.
structurally as well as functionally different.
structurally similar but functionally different.
structurally different but functionally similar.
The cell theory was given in year 1839 by Schleiden and Schwann. According to this theory all organisms are composed of cell and cells are the basic unit of life.
How did this theory help in the field of science?
It helped to study the working of cells.
It helped in curing diseases caused by cell.
It helped in restating the earlier theories on cell.
It helped in introducing the use of microscopes to study cell.
Match the items given in column-I with their role given in column-II and choose the correct option.
| Column-I | Column-II |
|---|---|
| A. SER | I. Increase the surface area |
| B. Golgi apparatus | II. Store oils or fats |
| C. Cristae | III. Excretion |
| D. Peroxisome | IV. Photorespiration |
| E. Elaioplasts | V. Synthesis of lipid |
A V; B III; C I; D IV; E II
A V; B III: C II; D IV; E I
A II; B III; C I; D IV; E V
A III; B IV; C I; D V; E II
Chromosomes having equal or almost equal arms are called
metacentric
acrocentric
polycentric
acentric.
Golgi apparatus is absent in
higher plants
yeast
bacteria and blue-green algae
None of the above
The best material for study of structure of cell membrane is
RBC of human
RBC of frog
cheek cell of human
liver cell of rat
Match column-I (scientists) with column-II (discovery) and select the correct option.
| Column-I | Column-II |
|---|---|
| A. Leeuwenhoek | I. First saw and described a living cell |
| B. Robert Brown | II. Presence of cell wall is unique to plant cells |
| C. Schleiden | III. Discovered the nucleus |
| D. Schwann | IV. All plants are composed of different kind of cells |
A I, B III, C IV, D II
A I, B III, C II, D IV
A III, B I, C IV, D II
A I, B IV, C II, D III
The diagram given below represent a filuid mosaic model of plasma membrance. Match the components marked as A, B, C, D and E in the diagram below from the list (i) to (vii).
- Sugar
- Protein
- Lipid bilayer
- Integral protein
- Cytoplasm
- Cell wall
- External protein
A - (i), B - (ii), C - (iii), D - (iv), E - (v)
A - (ii), B - (i), C - (iii), D - (iv), E - (v)
A - (i), B - (ii), C - (iii), D - (iv), E - (vi)
A - (i), B - (ii), C - (iii), D - (vii), E - (v)
Match column-I with column-II and choose the correct option.
| Column-I | Column-II |
|---|---|
| (Chromosome) | (Position of Centromere) |
| A. Metacentric | I. At the tip |
| B. Submetacentric | II. Almost near the tip |
| C. Acrocentric | III. At the middle |
| D. Telocentric | IV. Slightly away from the middle |
A III; B IV; C II; D I
A IV; B III; C II; D I
A I; B II; C III; D IV
A IV; B III; C I ; D II
The main organelle involved in modification and routing of newly synthesized proteins to their destinations is
chloroplast
mitochondria
lysosome
endoplasmic reticulum
Function of contractile vacuole in Amoeba is
excretion and osmoregulation.
digestion and respiration.
osmoregulation and transportation.
none of the above.
Match column-I with column-II and select the correct option.
| Column - I | Column - II |
|---|---|
| A. Golgi apparatus | I. Storage |
| B. Mitochondria | II. Photosynthesis |
| C. Vacuoles | III. Transport |
| D. Grana | IV. Secretion |
| .. | V. Respiration |
A - IV, B - V, C - I, D - II
A - I, B - II, C - IV, D - III
A - IV, B - I, C - II, D - III
A - I, B - II, C - III, D - IV
Centrifugation of a cell results in the rupture of the cell membrane and the contents compacting into a pellets in the bottom of the centrifuge tube. Bathing this pellet with a glucose solution yields metabolic activity including the production of ATP. One of the contents of this pellet is most likely which of the following?
Cytosol
Mitochondria
Lysosomes
Golgi bodies