Cell Structure

Front 1

Prokaryotic

Back 1

- Has no membrane bound organelles

- eg: bacteria

Front 2

Eukaryotic

Back 2

Contains membrane bound organelles that are held in place by protein filaments known as a cytoskeleton

Front 3

Apoptosis

Back 3

The self destruction of cells for the good of the whole organism. Known as programmed cell death

Two pathways:

1. Signals from outside the cell

2. Signals from inside the cell - mitochondrial pathway

Involves the release of caspase enzyme to fragment DNA

Front 4

Plasma membrane

Back 4

Fluid mosaic that controls the entry and exit of material.

Flexible

Phospholipid bilayer

Contains cholesterol and proteins

Semipermeable. Allows rapid absorption of lipid soluble substances and small substances such as water, carbon dioxide and oxygen.

Front 5

Membrane phospholipids

Back 5

Hydrophilic head.

2 hydrophobic fatty acid tails.

Front 6

Membrane cholesterol

Back 6

Fit between the phospholipids.

makes the membrane more flexible.

Gives rigidity to the membrane.

Front 7

Membrane Proteins

Back 7

Surface proteins

- glycoproteins are proteins with carbohydrates attached. They are involved in cell to cell recognition

Transmembrane proteins

- protein channels for the entry and exit of material

Front 8

Cell wall

Back 8

Rigid outrage layer surrounding the cell membrane.

Provides protection and shape.

Found in plants (cellulose), fungi (chitin), bacteria (peptidoglycan).

Prevents over expansion of the cell when water enters.

Front 9

Nucleus

Back 9

Contains the DNA which holds the code for the proteins.

Bound by a double membrane with pores.

Front 10

Cytosol

Back 10

A fluid consisting manly of water that contains dissolved substances.

cytoplasm = cytosol + organelles except nucleus

protoplasm = cytosol + all organelles

Front 11

Mitochondria

Back 11

The "powerhouse" of the cell. The site of cellular respiration which is the process that produces ATP.

Contains a double membrane. The inner membrane is highly folded. The fingerlike projections are called christae and the matrix is the space between.

Front 12

Ribosomes

Back 12

The site of protein synthesis.

Has no membrane.

Those on ER produce proteins for transport to other parts of the cell or for export.

Those that are free produce proteins for local use within the cell.

Front 13

Chloroplasts

Back 13

Capture radiant energy and transform it to chemical energy present in organic molecules.

Made of:

Grana - Stacks of membrane structures called thylakoids.

Stroma - Gel like matrix

Front 14

Endoplasmic reticulum

Back 14

A continuous folded plasma membrane creating a series of channels.

Rough - Has ribosomes attached. Makes and transports proteins within the cell.

Smooth - Site of phospholipid and fatty acid production.

Front 15

Golgi Body

Back 15

A network of folded membranes. Packages the protein into vesicles for transport across the plasma membrane and out of the cell.

Large numbers found in cells concerned with secretion eg. Glands.

Front 16

Lysosomes

Back 16

Fluid filled sacs containing dissolved digitise enzymes. These enzymes destroy unwanted cell parts or damaged molecules from within or outside the cell.

Front 17

Peroxisomes

Back 17

Small membrane bound organelles rich in the enzyme catalase and irate oxidase. Detoxify various toxic materials that entre the blood stream such as alcohol and hydrogen peroxide.

Found in plant and animal cells

Front 18

Endosomes

Back 18

Membrane bound organelles found in animal cells. Pass newly ingested material in the cell to the lysosomes for digestion.

Front 19

Vaculoles

Back 19

Membrane bound cavities used for storage.

Large in plants and small in animals.

Front 20

Cytoskeleton

Back 20

An internal framework of protein microtubules, microfilaments and intermediate filaments.

Maintains the shape of the cell, provides a support structure for components within the cell, aids the movement of materials within the cell and aids in cell replication.

Front 21

Occluding junctions

Back 21

Involves cell membranes coming together in contact with each other. There is no movement of material between cells.

Found in animal cells

Front 22

Communicating junctions

Back 22

Small, open protein lined channels that directly link the cytoplasm of adjacent cells, permitting passage of different substances (eg, salt ions, sugars, amino acids) and electrical impulses (eg, the control of the beating heart)

Found in animal cells

Front 23

Anchoring junctions

Back 23

Also called desmosomes. Help hold cells together in tissue that is subject to stretching ( skin, uterus).

Found in animal cells

Front 24

Plasmodesmata

Back 24

Cell to cell connection in plants. Allows for communication between a large number of cells. The plasma membrane between the two cells is continuous.