Cell The Unit of Life Test - 7

Mitochondria are double membranous structure. The inner membrane of mitochondria thrown into folds to form finger-like structureis called cristae.

The staining procedure developed by Gram viz., those that take up the gram stain are gram positiveand the others that do not are called gram negative bacteria.

Smooth endoplasmic reticulum (SER) differ from rough endoplasmic reticulum (RER) in absence of ribosome on the surface of endoplasmic reticulum.

Golgi apparatus is the important site of formation of glycoproteins and glycolipids.

The leucoplasts are the colourless plastids of varied shapes and sizes with stored nutrients. Leucoplast includes:

a) Amyloplasts storing carbohydrates.

b) Elaioplastsstoring oils and fats and

c) Aleuroplasts storing proteins.

In a mature cell, the vacuole may occupy as much as 90 percent of the cell volume, such that the rest of the cell contents are flattened against the cell membrane.

The chloroplast consists of a number of organised flattened membranous sacs called the thylakoids,Chlorophyll pigments are present in the thylakoids.

The cell wall of a young plant cell, the primary wallis capable of growth, which gradually diminishes as the cell matures and the secondary wall is formed on the inner (towards membrane) side of the cell.

An elaborate network of filamentous proteinaceous structures present in the cytoplasm is collectively referred to as the cytoskeleton.

The solutes may move across the membrane by the process of simple diffusion along the concentration gradient, i.e., from higher concentration to the lower.