The two subunits of ribosome remain united at a critical ion level of
Vacuole in a plant cell
1. is membrane-bound and contains storage proteins and lipids
2. is membrane-bound and contains water and excretory substances
3. lacks membrane and contains air
4. lacks membrane and contains water and excretory substances
In germinating seeds fatty acids are degraded exclusively in the
Which one of the following is not a constituent of cell membrane ?
Lysozyme that is present in perspiration, saliva and tears, destroys:
1. certain fungi
2. certain types of bacteria
3. all viruses
4. most virus-infected cells
Select the wrong statement from the following:
1. both chloroplasts and mitochondria contain an inner and an outer membrane
2. both chloroplasts and mitochondria have an internal compartment, the thylakoid
space bounded by the thylakoid membrane
3. both chloroplasts and mitochondria contain DNA
4. the chloroplasts are generally much larger than mitochondria
Which of the following statements regarding mitochondrial membrane is not correct?
1. The outer membrane is permeable to all kinds of molecules
2. The enzymes of the electron transfer chain are embedded in the outer membrane
3. The inner membrane is highly convoluted forming a series of infoldings
4. The outer membrane resembles a sieve
Which of the following statements regarding cilia is not correct ?
1. The organized beating of cilia is controlled by fluxes of Ca2+ across the membrane
2. Cilia are hair-like cellular appendages
3. Microtubules of cilia are composed of tubulin
4. Cilia contain an outer ring of nine doublet microtubules surrounding two single
The organelle common among prokaryotic and eukaryotic cell is
Which one of the following phenomena is commonly referred as 'cell drinking?