Cell Biology and Structure

It is correct because the cristae of mitochondria have the enzyme ATP synthetase for ATP manufacture.

Totipotency is the ability of a cell, such as an egg, to give rise to unlike cells and thus to develop into or generate a new organism or part.

In sponges (Porifera), food particles are ingested by choanocytes and then transferred to amoebocytes or thesocytes for storage and digestion.

 Pinacocytes are flattened cells containing many granules; capable of contracting. They are involved in the maintenance of the size and structure of sponge. They can expand and contract and slightly alter the size of the sponge. It can also produce collagen.

Integrins are receptors that mediate attachment between a cell and the tissues surrounding it, which may be other cells or the ECM. They also play a role in cell signaling and thereby regulate cellular shape, motility, and the cell cycle.

Cresyl violet is an organic compound with the chemical formula C₁₉H₁₈ClN₃O. It is used in biology and medicine as a histological stain. Cresyl violet is an effective and reliable stain used for light microscopy sections.

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Lysosomes are the single membrane-bound organelles found only in animal cells. They have acidic pH and acid hydrolases enzymes that perform degradative function.

Chromatophores are absent in the plant cells as these are the specialised photosynthetic structures present in the cyanobacteria and photosynthetic bacteria only.

Peroxisomes are single membrane bound cell organelles that contain oxidases and catalases enzymes. The enzyme catalases protects other cell organelles from the toxic effects of H₂O₂ by converting it into water and oxygen.

Vacuoles are the important cell organelles present in the plant cells. They usually consume about 30 percent of the cell’s volume. Vacuoles are important as they help in adjusting size and turgor pressure of the plant cells. Vacuoles are the cell organelles that share similarity with the lysosomes of animal cells as both contain degradative enzymes for breaking down macromolecules. In plants, vacuoles also serve as storage compartments for metabolites and nutrients.

Streptomycin and erythromycin are types of antibiotics that specifically act on the 70s ribosomes of prokaryotes and thus do not act on the 80S ribosomes of eukaryotic cells. However, mitochondrion contains 70 S ribosomes, it is most likely to get affected if it is treated with streptomycin or erythromycin antibiotic.

Membrane proteins are produced on the rough endoplasmic reticulum and are carried forward with the help of membrane-bounded transport vesicles. Subsequently, these proteins are carried to the luminal cavity of the golgi complex, where they are processed.

Blood cells, particularly red blood cells, lack mitochondria.

Golgi complex consists of a series of flattened membrane vesicles or sacs surrounded by spherical membrane vesicles. The three well-defined regions that are present in the stack of the flattened golgi sac include cis, medial and trans. Secretory proteins and membrane proteins from the rough endoplasmic reticulum first reach the cis region of the golgi complex, and then move to the medial region and ultimately to the trans region. While passing through all these regions, they undergo modifications by the specialised enzymes of the sacs.