gaps or breaks in cell cycle. No special events occur during these phases except the size of the cell may increase.

organelles involved in the integration of pro-apoptic signals except

It is a lipid bilayer. It also consists of proteins and small amounts of carbohydrates

fluid and dynamic

semi permeable, only selected compounds are allowed to pass through from out- side

The modification of this organelle results in formation of specialized structures like axon of nerves, microvilli of intestinal epithelium and tail of spermatids.

The outermost structure of the cell that decides its contour is the cell membrane.

surrounded by double-layer membrane of about 250-400 Å thick

two layers of nuclear membrane which when fuse periodically, produce nuclear pores

the information centre of eukaryotic cell.

More than 90% of the cellular DNA is present in this organelle

this organelle is mainly concentrated in the form of chromosomes.

number of chromosomes human cell contains

other term is nuclear matrix

It contains enzymes involved in the synthesis of DNA and RNA

small dense bodies present in the nucleus

The extra nuclear cell content that possess both orgenelles and other material constitutes this organelle

Centre of the cell

Sometimes soluble portion of the cell is referred as

this organelle accounts for 70-75% weight of the cytosol

Numerous enzymes, proteins and many other solutes are found in this organelle

the main site for glycolysis, HMP shunt, activation of aminoacids and fatty- acid synthesis.

ellipsoidal in shape and can assume variety of shapes

The length of this organelle is about 7 microns and has a diameter of 1 micron

Mitochondria consist of outer and inner membranes: This membrane is composed of equal amount of protein and lipids.

Mitochondria consist of outer and inner membranes: This membrane functions as a limiting membrane and permeable to many compounds.

Mitochondria consist of outer and inner membranes: This membrane consists of 75% protein and remainder is lipid.

It is present in aerobic state and absent in anaerobic state

Exposure to cold makes this organelle increase by 20-30% in liver cells.

In highly metabolically active cells, this organelle is more and large.

In liver cell, this organelle is scattered. In muscles, this organelle is parallely arranged

the power house of the cell. It is responsible for the production of energy in the form of ATP

reactions of gluconeogenesis and urea cycle occur here. also, this organelle is capable of synthesizing some of its proteins.

In humans, this organelle is derived from mother only. Hence, origin of mother of humans has been traced.

The second largest structures in the cell.

surrounded by a membrane and are called as ‘Suicidal bags’ of the cell.

rich in hydrolytic enzymes which are active at acidic pH

this organelle digests the molecules brought into the cell by phagocytosis.

Macrophages are rich in this organelle

involved in bone remodelling and intracellular digestion

Disease, shock or cell death causes rupture of this organelle and release of enzymes

responsible for cell death of larval tissues.

its enzymes are released to cause uncontrolled destruction of surrounding tissues.

its proteases cathepsins are involved in spreading of cancer (metastasis).

involved in integration of pro-apoptic signals.

They are small vesicles present in cytoplasm

contain enzymes of H2O2 metabolism

Glycerophospholipids are also synthesized in this organelle

he enzymes of H2O2 catabolism present in peroxisomes

small vesicles surrounded by a membrane and called as "microbodies"

an extensive network of membranes in the cytoplasm.

contains several small vesicles, which are pinched off from the flattened margins of membranes.

involved in secretion

Material produced in the cell for export is processed by

involved in protein targeting. It directs proteins to be incorporated into membranes of other subcellular structures. It is also involved in glycosylation and sulfation of proteins.

involved in integration of proapoptic signal. It generates preapoptic mediator ganglioside GD3.

consists of cluster of paired cytomembranes.

coated with ribosomes.

involved in protein synthesis (aside ribosomes)

It is continuous with outer nuclear membrane.

absence of ribosomes.

of intestinal cells is involved in formation of triglycerides.

the site of steroid formation

membrane enclosed vesicles containing fluid. mostly they contain nutrients.

It is continuous with rough endoplasmic reticulum.

Some mammalian cells contain thin coat known as

flexible and sticky; the adhesive properties of cell and organization of tissue is controlled by

Same as that of myosin of skeletal muscle

involved in the maintenance of cell shape, cell division, cell motility, phagocytosis, endocytosis and exocytosis.

They are not involved in movement of cell. They are stable

components of cytoskeleton. Neurofilament of neurons, glial filaments of glial cells

and keratin of epithelial cells are some examples

cell cycle: Division of a cell into two daughter cells requires duplication of DNA

They are actin like filaments. They form loose web beneath cell membrane.

it can be few hours to months or even years.

many events take place in this phase of cell cycle. At the end mitosis cell divides into two daughter cells. The daughter cells are in G1-phase.