Which of the following is not the function of cell wall?
- Provides shape to the cell.
- Protects the cell from mechanical damage and infection.
- Helps in cell to cell interaction.
- Provides barrier to undesirable macromolecules.
Only (i)
Only (iv)
Only (ii), (iii) and (iv)
None of the above
Correct Answer :
D. None of the above
All the given function is related to cell wall. Cell wall is a very tough, flexible and fairly rigid layer that surrounds some types of cells. It surrounds the cell membrane and provides these cells with structural support and protection. In also acts as a filtering mechanism.
Related Questions
Given below are some characters of a cell organelle identify the correct organelle which shows all the characters described above.
- It is a membrane bound space found in the cytoplasm.
- It is bound by a single membrane called tonoplast.
- It contains water, sap, excretory products and other materials not useful to the cell.
- It has higher concentration of sap than the cytoplasm.
Golgi apparatus
Lysosomes
Endoplasmic reticulum
Vacuoles
Which of the following option correctly match A, B, C, and D indicated in the given sectional view of chloroplasts.
A - Thylakoid, B-Stromal lamella, C - Stroma, D - Granum
A - Granum, B - Thylakoid, C - Stromal lamella, D - Stroma
A - Thylakoid, B - Granum, C - Stromal lamella, D - Stroma
A - Granum, B - Thylakoid, C - Stroma, D - Stromal lamella
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
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.
Choose the incorrect match.
Nucleus RNA
Lysosome Protein synthesis
Mitochondria Respiration
Cytoskeleton Microtubules
Which of the following statements are incorrect ?
- Plant cells have centrioles which are absent in almost all animal cells.
- Ribosomes are the site of protein synthesis.
- The middle lamella is a layer mainly of calcium carbonate which holds the different neighbouring cells together.
- In animal cell, steroidal hormones are synthesized by smooth endoplasmic reticulum. Of the above statements
(i) and (iii)
(iii) and (iv)
(ii) and (iv)
(i) and (iv)
pH of vacuolar cell sap is
neutral and isotonic.
alkaline and isotonic.
acidic and hypertonic.
equal to cytoplasm and isotonic.
Which of the following pair lack the unit membrane?
Nucleus and E.R.
Mitochondria and chloroplast
Ribosome and nucleolus
Golgi body and lysosome
Read the folowing statements and identify the correct option.
- Contractile vacuole takes part in osmoregulation and excretion.
- Food vacuole is formed by engulfing the food particles.
- The vacuole is bound by a double membrane called tonoplast.
- Vacuole can occupy upto 90 percent of the volume of the cell.
(i) and (ii)
(ii) and (iv)
(i), (ii) and (iv)
None of the above
Which cellular structure helps in transferring genetic information from one generation to another?
W
X
Y
Z
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.
Function of RER is
autolysis
protein synthesis
lipid synthesis
carbohydrate synthesis
Which of the following statement of a bacterial cell is/are correct?
- Mesosome is formed by the extensions of plasma membrane into the cell.
- The pili are elongated tubular structures made up of a protein.
- Flagellum is composed of filament, hook and basal body.
- Ribosomes are about 30 nm by 50 nm in size.
(i), (ii), (iii)
All of the above
(ii) & (iv)
None of the above
According to widely accepted fluid mosaic model cell membranes are semi-fluid, where lipids and integral proteins can diffuse randomly. In recent years, this model has been modified in several respects. In this regard, which of the following statements is incorrect?
Proteins in cell membranes can travel within the lipid bilayer.
Proteins can also undergo flip-flop movements in the lipid bilayer.
Proteins can remain confined within certain domains of the membrane.
Many proteins remain completely embedded within the lipid bilayer.
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.
Chromosomes having equal or almost equal arms are called
metacentric
acrocentric
polycentric
acentric.
Plastids storing fat are called
Elaioplasts
Sphaerosomes
Aleuroplasts
Pyrenoids
The given diagram shows the types of chromosomes (labelled as A, B, C & D) based on the position of centromere.
Which one is the correct option for the labelled chromosomes. A, B, C and D ?
A Telocentric chromosome, B Acrocentric chromosome, C Submetacentric chromosome, D Metacentric chromosome
A Acrocentric chromosome, B Telocentric chromosome, C Metacentric chromosome, D Submetacentric chromosome
A Submetacentric chromosome, B Metacentric chromosome, C Telocentric chromosome, D Acrocentric chromosome
A Metacentric chromosome, B Submetacentric chromosome, C Acrocentric chromosome, D Telocentric chromosome.
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
Cell sap is a
living content of cytoplasm.
nonliving content of cytoplasm.
nonliving content of vacuole.
living content of vacuole.
The main organelle involved in modification and routing of newly synthesized proteins to their destinations is
chloroplast
mitochondria
lysosome
endoplasmic reticulum
Which of the following is incorrect ?
Mycoplasma is the smallest cell (0.3 �).
Bacteria are 3 to 5 �m in size.
The largest cell is the egg of an ostrich.
Nerve cells are some of the smallest cells.
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
_______________ is the important site of formation of glycoproteins and golycolipids.
SER
Lysosome
Golgi apparatus
Mitochondria
The figure below shows the structure of a mitochondrion with its four parts labelled (A), (B), (C) and (D).
Select the part correctly matched with its function.
Part (D): Outer membrane Gives rise to inner membrane by splitting.
Part (B): Inner membrane Forms infoldings called cristae.
Part (C): Cristae Possess single circular DNA molecule and ribosomes.
Part (A): Matrix Major site for respiratory chain enzymes.
Which of the following terms is not correctly matched with its feature?
Osmosis Movement of water by diffusion.
Nucleoplasm Site of active synthesis of ribosomal RNA.
Mesosome Infolding of cell membrane and characteristics of eukaryotes.
Pili Elongated tubular surface structures (made of special protein) of bacteria.
The membrane of the erythrocytes has approximately ___% of proteins and ___% lipids.
42, 50
52, 40
50, 50
60, 40
Which of the following statements is/are correct ?
- The shape of the cells may vary with the function they perform.
- Human RBC is about 7.0 ??m in diameter.
- Cytoplasm is the main area of cellular activities.
- Various chemical reactions occur in cytoplasm to keep the cell in the living state.
(i), (ii), (iii) and (iv)
Only (i) and (ii)
Only (iv)
None of the above
Most of water, in mature plant cells occurs in
nucleus
cell wall
vacuoles
cytoplasm
Golgi apparatus is absent in
higher plants
yeast
bacteria and blue-green algae
None of the above