Cell Structure

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Plasma Membrane

Plasma Membrance - The Fluid Mosaic Model

The plasma membrane is a permeable membrane around the cell which controls any exchange in and out of the cell.
The fluid mosaic model, suggested by Singer and Nicholson, said that the plasma membrane has a phospholipid bilayer, two layers with the hydrophobic tails together and the hydrophilic heads apart.
It contains glycolipids, glycoproteins, transmembrane proteins and surface proteins.
This membrane also acts as a barrier against certain objects or substances.

Inside an Animal Cell

Nucleus

The largest organelle within the cell.
It's enclosed by two membranes in an envelope.
The Nucleus contains chromatin, which is the extended form taken by chromosomes during interphase, as well as a nucleolus.

Endoplasmic Reticulum (ER)

A system of flattened membranes called cisternae (note: I spelt it wrong in the diagram, sorry).
It's a continuous single membrane which is also the nuclear outer-membrane.
When ribosome's are found on its surface its known as a rough ER and it transports any proteins made by the ribosome's.

Mitochondria

Site of Respiration (or part of it).
Surrounded by two membranes, the inner folded forming cristae.
Contains ribosome's, circular DNA molecule and a matrix.

Ribosomes

Site of protein synthesis.
Very small organelles consisting of a larger and a smaller subunit.

Golgi Body/Apparatus

Similar in structure to the endoplasmic reticulum (ER) but is more compact and is made up of flattened sacks.
It's functions include transporting and storing lipids, producing glycoprotein, forming lysosomes and producing secretary enzyme.

Lysosome

This contains digestive enzymes from the remainder of the cell and one of its purposes is destroy old organelles.

Plant Cell

Chloroplasts

A Chloroplast diagram showing the circular DNA, ribosomes, granum, stroma and chloroplast envelope.

Chloroplasts are large organelles, usually in a biconvex shape, and about 4-10μm long and 2-3μm wide.
Within plants most chloroplasts are found in the mesophyll cells of leaves.
The stages of photosynthesis take place within the chloroplast, stage 1 within the granum and stage 2 within the stroma.

Differences between Animal and Plant Cells

Structure	Animal Cell	Plant Cell
Plasma Membrane
Nucleus
Endoplasmic Reticulum
Mitochondria
Ribosome's
Golgi Body/Apparatus
Chloroplasts

Illustrated Revision Notes

Click on the images below to enlarge them. Each picture below was an A4 sheet of paper and was cleverly illustrated by Charlotte Turtle in preparation for her exams. I've put them on Biology-Innovation because I think they provide a unique way of looking biological subjects.