Q&A

Q1. Which of the following equations is/are correct?

a) (Cell – cell organelles) = cytosol b) (Cytosol + cytogel) = protoplasm c) (Cell – nucleus) = cytosol d) (Cytoplasm- cytosol) = cell…

Qs. Which of the following cell organelles has never been isolated? a) Lysosomes b) Chloroplast c) Peroxisomes d) Spherosomes e) Vacuole

The correct answer is d). Spherosomes are very small organelles which are detached from ER. They are found only in cells of higher plants,…

Qs. Decode the given protein sequence: “WATER”. What is the overall charge present on this protein. a) 0 (neutral) b) +1 c) -1 d) +2

Ans. Please note that “W ” is the single letter code for “Tryptophan”, ‘A’ for “Alanine”, ‘T’ for “Threonine” , ‘E’ for “Glutamic acid”…

A mixture is having 5 components A, B, C, D and E of size 2, 4, 6, 8 and 10 µm. This mixture is applied to a column having beads of size, 2, 4, 6, and 8 µm. After this, mobile phase is applied. The value of Partition coefficients (Kd) of sample components in stationary and mobile phase will be in the ratio: a) E>D>C>B>A b) A>B>C>D>E c) D>C>B>A>E d) A>D>B>C>E

Correct Answer is b. Explanation: Distribution coefficient = (concentration of component in stationary phase)/ (concentration of component in mobile phase). It is represented by…

Digestive system of the cell – Lysosomes

Discovery and nomenclature of lysosome: They were discovered by De Duve in 1955. Initially these organelles were named as peri-canalicular dense bodies based on…

Why lysosomes were called suicidal bags???

Why lysosomes were called suicidal bags??? Initially De Duve observed that hydrolytic enzymes of lysosomes are capable of digesting the entire cell. So, he…

Concept of Epigenetics and paramutation

“epi” means “over”; epigenetics means “over the range or beyond the range of genetics”. This term is used for those phenotypic or physiological changes…

What are Kupffer cells? Which organelle of Kupffer cells is most specialized?

Kupffer cells are specialised macrophages present in liver. They aid in the breakdown of old and worn out RBCs. Lysosome is the most specialised…

Balphakram National Park is in which state of India? a) Orissa b) Meghalaya c) Nagaland d) Kerala…

Meghalaya. Balphakram National Park is near the Garo Hills in Meghalaya; it is also close to the boundary of Bangladesh.

“Cell biology” assignment based on NCERT- Class XI

Assignment based on “The Cell”- Class XI CBSE… Part A: State whether the given statements are true or false. Give reasons for false statements….

What is the difference between phago-lysosome and cyto-lysosome?

Phago-lysosome Cyto-lysosome These are also known as hetero-lysosome or heterophagic vacuoles. Also known as autophagosome, autolysosome or autophagic vacuole. Substances are also brought into…

How much DNA is present in 100mg soil?

Size of bacterial genome = 130 kbps to 14 Mbps. 1 gm (1000 mg) soil contains at least 1 billion bacteria. 100 mg soil…

Which organelle of the cell was previously named as peri-canalicular body.

The answer is lysosomes. Initially lysosomes were named as peri-canalicular dense bodies. This name was based on their location inside the cell. Peri means…

If you remove a set of cells from an early embryo, you observe that the adult organism lacks the structure that would have been produced from those cells. Therefore, the organism seems to have undergone a) autonomous specification b) conditional specification c) Morphogenic specification d) Syncytial specification

a) Autonomous specification. Explanation: Autonomous specification occurs in most invertebrates. The fates of blastomeres in early developmental stages is invariant (unchangeable). In this, the…

Genetic diversity does not arise from a) need or want b) hybridisation c) crossover d) mutations

a) need or want (is the correct answer). Please note that hybridisation, crossover and mutations all result in mixing of gene components leading to…

What is the difference between onion and whitefish cells and the cells in the testes?

How have human cultural practices influenced the patterns of infectious diseases?

The disease which is spread from person to person is known as infectious disease. In this regard, an example of Ebola virus outbreak can…

A protein domain a) cannot have beta sheets. b) can fold only in the presence of the rest of the protein. c) is always composed of multiple peptides. d) can be disordered.

Ans… a) is false. Protein domains can have beta barrel. b) is also false. Protein domains are autonomous structures and can fold independently. c)…

Explain why tyrosine is classified as non-essential but most books actually call it a mis-classification

Ans: A non-essential amino acid is one which is synthesized in the body. Tyrosine is synthesized in the body from Phenylalanine, which is itself…