Cells Part II

Cells II

Cell Theory1. The cell is the smallest unit of life.

The cell carries out all life processes

2. All organisms are made from one or more cells.CellsTissuesOrgansSystemsOrganism

3. Cells arise from pre-existing cells.DNA in each cell contains all the information necessary to produce offspring

All cells have: Cell membrane Surrounds, contains, protects Cytoplasm “Cell gel” fills interior of cell Ribosomes Help make proteins for cells DNA Contains instructions for cell

Two Categories of Cells Prokaryotes “Before” nucleus Simple structure Bacteria Archaebacteria

Eukaryotes True nucleus holds DNA Many cell parts with

special functions One cell or

multicellular organisms Plants! Animals! Fungi!

Single-cell organisms!

Eukaryotic cells are larger and more complex than prokaryotic cells

Eukaryotic cells have organelles that perform special functions:

Manufacture cell products

Breakdown & maintenance

Convert energy Movement,

support Communication

Think as you study cell parts: What does it look like? What is its function? What other organelles does it work

with? How does the structure of this

organelle allow it to do its job? Is it in Animals? Plants? Other?

“Generic” Animal Cell

Boundary / Protection

Cell Membrane: Controls what goes in and out

Cytoplasm / Cytosol: Cell GelCytoplasm fills cell Organelles are suspended in matrix

Information

Nucleus: Control Center for the Cell

Contains DNA packaged into chromosomes

Nucleus is connected to important endomembrane structures

Manufacturing

Ribosomes: Workbench for making proteins

Endoplasmic Reticulum: Internal transport system of cell

2 forms of ER:Rough ER Ribosomes

attached to ER give it a rough appearance

Helps synthesize proteins

Transports proteins within cell

Smooth ER Transports Stores calcium Involved in making

lipids

Golgi body: Packages and Ships Cell products

Protein Synthesis

Making proteins is one of the most important jobs of the cell!

Maintenance

Lysosomes: Clean up crew;Baggies of powerful digestive enzymes get rid of old cell parts, bacteria

Energy production

Mitochondria: Powerhouse of the cell

Extract energy from glucose to provide energy for cell functions

Structure and movement

Cytoskeleton

3 sizes of fibers form skeleton of cell Produce shape & create movement

Plant Cells

Plant Cell

Plants have specialized organelles not found in animal cells:

Rigid cell wall: supportChloroplasts: capture energy

from sunLarge vacuole: storage (water,

sugars)

Chloroplast: Use sunlight to make sugars

Photosynthesis

Chloroplasts

Plant Cell Vacuole: Stores water and food

Plant Cell Walls: Support and Protection

A few examples of specialized cells

from complex organisms