Test: Cell Structure & Functions- 2 - UPSC MCQ

Cell membrane is also called as cell membrane or PLASMA membrane. It forms the outer covering of the cell made up of protein and fat. It is semi-permeable in nature.

The transfer of traits from one generation to next generation is called inheritance. Inheritance is carried out by gene located in nucleus of the cell.

Total living substance in cell is protoplasm... protoplasm is made up of cytoplasm and nucleus / nucleoplasm... [ Protoplasm = cytoplasm + nucleoplasm ] blood is not present in cell.

Chromosomes are thin thread like structure present inside nucleus of the cell. Chromosome consists of DNA and protein. Genes are located on chromosome.

The fluid present between cell membrane and nucleus is called cytoplasm. Cytoplasm is thick fluid medium in which different cell organelles floats.

Permanent vacuoles are found in plant cells and fungi cells. The permanent vacuole of Xylem cells join together to form the xylem.

Fission, in biology, is the division of a single entity into two or more parts and the regeneration of those parts to separate entities resembling the original.For unicellular organisms, cell division is the only method used to produce new individuals. In both prokaryotic and eukaryotic cells, the outcome of cell reproduction is a pair of daughter cells that are genetically identical to the parent cell. In unicellular organisms, daughter cells are individuals.

Cells has ability to extract chemical energy from food molecules. The energy present in food molecules like glucose undergo respiration to produce chemical energy in form of ATP.

Robert Hooke in 1665 observed thin slices of cork under a simple magnifying device. He observed box-like structures and named them ‘cells’. This is because these structures reminded him of the cells in a monastery.

The membrane of nucleus is porous so it allows transport of specific proteins. Nucleus is also called as brain of the cell.

True Statement about Cells:
A single cell can perform all the functions in a unicellular organism.
Explanation:
- Cells are the basic structural and functional units of all living organisms.
- Unicellular organisms, such as bacteria and protozoa, are composed of a single cell.
- Unlike multicellular organisms, where different cells perform specialized functions, a single cell in a unicellular organism is capable of performing all the necessary functions for survival.
- This includes processes like respiration, reproduction, digestion, and response to stimuli.
- The cell membrane of a unicellular organism allows it to exchange nutrients and waste materials with its environment.
- The genetic material present in the cell's nucleus or other parts of the cell allows for the synthesis of proteins and other necessary molecules.
- Overall, the single cell in a unicellular organism is responsible for carrying out all the essential life processes, making the statement true.

Plasma membrane is a bilayered membrane made up of protein and lipid. It is selectively permeable to different substances.

Flagella is a locomotory organelle in protozoa. Flagella is long hair like projection on the body of some protozoa.

Mitochondria is called as powerhouse of the cell because it contain enzyme for cellular respiration in which energy is released in form of ATP.

Cell membrane is a selectively permeable membrane because it allow some substance to cross but prevents the other.

The cell wall of plant is made up of cellulose. Cellulose is a complex sugar which cannot be digested by human beings.

The cell which lack well developed nuclear membrane is called prokaryotic organism. Blue green algae and amoeba are example of prokaryotic organism.

Centrosomes are present only in animals cell. Centrosome produces fimbriae that help in cell division. Chromosome and ribosome are present in both animal and plant cell.

The colour of the plant is due to presence of different kinds of plastids. Chromoplast provides all colours except green and white.

Dictyosomes are present only in plant cell. Centrosomes is present in animals cells only and mitochondria and ribosomes are present in both plant and animal cell.