I. Introduction to the Cell “With the cell, biology discovered its atom.” –Jacob

A. The cell is the smallest unit that can carry on all processes of life.1. make energy2. produce waste3. reproduce4. respond to stimulus5. evolve

B. Unicellular: one celled organisms…Protists and Bacteria C. Multicellular: more than one celled organisms D. Discovery of the cell was made possible by the

development of glass lenses.1. Leeuwenhoek (Dutch)- first person to observe living

cells2. Hooke (English)- observed cork from the bark of an

oak tree. a. The cells looked like empty compartments similar to cells in a monastery so he named them “cells”

II. Formation of the Cell Theory A. What is the cell theory?

1. all living things are composed of one or more cells2. cells are the basic unit of life3. cells only come from other cells

B. What they used to believe: Spontaneous Generation (living things come from nonliving things)1. mud produces fish2. puddles of water produce microorganisms3. rotting meat produces flies4. stale bread produces mold

C. A series of experiments were conducted to prove Spontaneous Generation wrong.

http://www.sumanasinc.com/webcontent/animations/content/scientificmethod.html

III. Cell Diversity A. Shape

1. different shapes because they have different functions a. nerve cells – long extensions to receive and give

messages

b. flat skin cells – to protect c. white blood cells change shape so they can move through narrow openings

B. Internal organization 1. Eukaryotic Cells 2. Prokaryotic Cells nucleus no nucleus membrane bound organelles no membrane bound

organelles

Ex: plants, animals, fungi, protists Ex: Bacteria

C. Size: there is a limit of size due to the speed at which materials need to get to the center of the cell

D. Difference between plant and animal cells:

Plant cell Animal cell Thick rigid cell wall No cell wall

Rectangular shape No rigid shape (roundish)

Has chloroplasts No chloroplasts

Large central vacuole Some have small vacuoles

IV. Parts of the Cell A. Cell Membrane

1. Separates the cell from its external environment2. Gives shape and flexibility to the cell3. Made of 2 layers (“phospholipid bilayer”)4. Made of fats (phospholipids) and proteins5. Cholesterol is also a part of the membrane6. “Fluid Mosaic Model” is how scientists refer to its structure7. Drawing:

B. Cytoplasm: space within the cell excluding the nucleus 1. jelly like material that contains water, salt, sugars, fats and proteins = cytosol2. It is always moving

C. Organelles—“little organ”, each performs a specific activity1. Refer to chart on next page.

Nucleus is purple, cytoplasm is pinkish. This is a lymphocyte

The black stuff

Contains DNA

Makes ribosomes

Protects the nucleus

Allows things to go in and out of the nucleus

Not membrane bound

Makes proteins

Rough because it is covered in ribosomes

Makes, packages, and transports protein

Packages and transports protein and fat

Where polysaccharides are made, packaged, and transported

Attaches carbohydrate tags to cell membrane proteins

Contains digestive enzymes

Breaks down foreign material, old cell parts, and food.

Where food (glucose, fatty acids) is used to make energy (ATP)

Tubulin…the protein that makes up a microtubule

Hollow tube that makes up cytoskeleton.

Gives cell its shape, helps in movement and helps in cell division

Solid protein thread that makes up cytoskeleton

Adipose Tissue (fat cells store fat in a large central vacuole)

Organelle that stores food, waste, and/or water.

Plants have 1 large one and animals have many small ones.

Tail-like structure

Moves the cell

Tiny hairs on the cell surface

Moves the cell OR

Moves things around the cell