Biology 5090 - cell biology

plant cell

Contains chloroplast, cell membrane, cell wall, vacuole, ribosomes, mitochondria, cytoplasm, nucleus.

Animal cell

Contains cell membrane, cytoplasm, nucleus, mitochondria, ribosomes.

Bacterial cell

Contains cell wall, cytoplasm, flagella, plasmids, single stranded DNA, ribosomes.

Never contain mitochondria, chloroplasts, or genetic material in a nucleus.

Cell

• Basic building block of life.

• Smallest unit of life that can replicate independently

• Cells are made up of sub-cellular structures aka organelles

• Animal and plant cells grow, whilst bacteria asexually reproduce ( binary fission).

Eukaryotes

Contain DNA in a nucleus

Example: plant and Animal cells

Prokaryotes

No nucleus, loose DNA.

Example: bacterial cell

Cell membrane

Controls which substances move in and out of the cell

Made up of lipids and proteins.

Nucleus

Contains genetic material => hence controls activity of the cell

• it controls cell activities such as cell growth and the repair of worn-out parts.

• it is essential for cell division. Cells without a nucleus, like the red blood cells

of a mammal, are unable to divide.

Cytoplasm

• Jelly like substance that holds the organelles in place.

• Chemical reactions occur here

Mitochondria

Provide cells with energy they need to function.

By the breakdown of sugars like glucose in aerobic respiration which releases energy.

Cell wall

• Rigid

• Made of cellulose

• Strong, to provide support and structure and prevent bursting.

Ribosomes

Site of protein synthesis

Vacuoles

Contain cell sap ( mixture of sugars salts and water )

Chloroplast

Where photosynthesis takes place, contains the green pigment chlorophyll which absorbs light energy and converts it into chemical energy

Plasmids

Carry extra genes, used in genetic engineering

Flagella

Propel the bacteria

Organelles

Sub cellular structures that perform a specific job in the cell