Why should we learn about cells?

• Protects cells to prevent infection and other harmful effects
• Observe cells to diagnose diseases
• Treat cells to heal illness
• Stop harming cells through our choices and actions

Types of cells:

Eukaryotes (true cells):

• cells with a nuclear membrane surrounding the nucleic acid
• e.g. plant and animal cell

Prokaryotes:

• Cells with no nuclear membrane
• e.g. bacteria and cyanobacteria (blue-green)

By breaking an intermolecular bond, you create a different state of matter (e.g. two water molecules broken apart by heat would create water vapor).

The DNA in a bacteria is called a Plasmid. Viruses don't have the ability to reproduce itself therefore is not considered a cell. They reproduce  by injecting DNA into a host cell which then explodes - killing the host cell - releasing all new born viruses.

Incubation period: time for a virus to reproduce (e.g. when you're contagious)

The most contagious time is usually before symptoms start to show. 

The functions of a cell:

• to grow
• to repair and heal
• to go through cell division and reproduce

For one cell birth there has to be one cell death. Older cells make more mistakes which is why older people have more diseases. 

Do cells live forever?

• No, after a certain number of cell divisions all cells die by committing suicide (apoptosis).

When a cell is not functioning properly and cannot be fixed, the cell releases the enzymes in the lysosome to sacrifice itself for the overall health of the organism. It disintegrates all organelles within the cell.

• Cells also die by injury caused by mechanical forces or toxic chemicals.

Reasons for apoptosis:

• To eliminate cells that threaten the overall health of a multicellular organism
• Part of normal development

Plant cells have very defined, boxy shapes because of the cell wall. The cell wall is made of cellulose. Glucose helps you absorb waste much easier. Vacuoles in plant cells are very large to store water, nutrients, etc.

Cytoplasm: water, any other fluid, waste, etc. inside of the cell wall.

Turgor Pressure: when the fluids push up against the cell wall to keep it up-right so it doesn't wilt.

Mitochondria: turns everything into a usable source of energy.

Ribosomes are not membrane bound and carry protein. They sit on top of the endoplasmic reticulum. They just store energy and are the smallest organelle in a cell. The endoplasmic reticulum with ribosomes on top make it "rough".

Chloroplast gives plants its colour. 

RNA: ribonucleic acid. (inside nucleolus)

DNA has to be protected at all times. (deoxyribonucleic acid) 

mRNA: messenger inside the nucleolus that tells the cell to produce proteins. It's a strand of code.

rRNA: comes to translate and read the code, calls out tRNA.

tRNA: carries a specific amino acid to come hook up the message. It's like a taxi, it picks up the amino acid, drops it off, then goes to get another one.

Our body can have up to 20 amino acids. 12 are produced by our bodies and 8 come from our diets.

Only animal cells have lysosomes and centrioles. Double layers are all membrane bound.