Cells are the basic unit of all living things.

Nucleus – contains DNA, regulates the functions of the cell.

Plasma membrane - regulates what goes into and out of the cell.

Mitochondria – where cellular respiration occurs.

Ribosomes- Make proteins

Look like little dots

Structure III

Cell wall – made of cellulose, protects plant cell and gives it shape.

Vacuoles – store food, water or waste. Large in plant cells, small in animal cells.

Chloroplast – where photosynthesis occurs.

Cells Tiss

ues Organs

Organ syste

ms

Nerve cells

Branching

structure is well

suited to

carrying nerve

impulses

through the

body.

Red blood cellssmooth disk shape is well suited to traveling through blood

vessels.

Muscle cells need a great deal of energy, so they have many

mitochondria located in them.

Plant cells Cell wall Large vacuoles Chloroplasts Rectangular

shape

Animal cells

No cell wall Small vacuoles No chloroplasts Any shape

1) Prokaryotes- No nucleus (no

nuclear membrane)- Ribosomes- No membrane

bound organelles- Small & primitive- Circular DNA (one

chromosome)

2) Eukaryotic- Nucleus (nuclear

membrane)- Membrane bound

organelles, have ribosomes

- Large & complex

Messages can

travel from one

nerve cell to

another.

•Homeostasis: maintaining a stable internal environment

Sweating

Blood vessels

Dilate (get

bigger)

Shivering Blood vessels

constrict Hair stands on end

Buffers in blood help to keep blood from becoming too acidic or too basic.

Insulin removes glucose from your blood by turning it into glycogen in your liver and muscles.

Glucagon puts glucose into your blood by converting glycogen into glucose.

Too much water?Urinate frequently and it is very dilute

(urine is clear)

Too little water?Urinate infrequently and it is very

concentrated (urine is dark yellow)

1. Passive transport(requires NO energy)a. Diffusionb. Osmosis

2. Active transport(requires energy)

The movement of molecules from an area of high concentration to an area of low concentration.

Special type of diffusion (of water!) Movement of water thru a membrane Requires no energy Water moves from high concentration to

low concentration

Movement of molecules & ions from an area of low concentration to high concentration.

Requires Energy (ATP)

Allows small molecules to pass through but not large ones

1st picture – RBC’s in salt water2nd –RBC’s in slightly salty water3rd – RBC’s in distilled water

RBC= red blood cells