Chapter 1 C

Cells: The Basic Units of Life

Section 1

• The Diversity of Cells:

• Cell – the smallest unit that can perform all the processes necessary for life

• - come in many different sizes and shapes

Cells and the Cell Theory…..• Robert Hooke – first to describe cells (1665)

- built simple microscope

- looked @ cork (saw little rooms and called them cells)

Finding cells in other organisms….. • Anton van Leeuwenhoek – 1673

- made microscope

- looked @ pond scum (animalcules/protists)

- looked at animal blood (noticed different shapes in different animals)

However…..

• Zacharias Jannsen - built 1st compound scope

The Cell Theory…..

• Matthias Schleiden – German- all plant tissue made of cells

The Cell Theory…..

• Theodore Schwann- German- concluded that all animal tissue is made of cells

The Cell Theory…..• Rudolf Virchow –

- German- Concluded all cells come from other cells

The Cell Theory…..

1. All organisms are made of cells

2. The cell is the basic unit of life

3. All cells come from other cells

Cell Size…..

There are a few large one – yolk of an eggMany smaller ones –

size is controlled by the surface area to volume ratio

Parts of a Cell…..

• Cells come in many different shapes and sizes

• Cells have many different functions

All cells have these parts…..

• Cell Membrane – protective layer around cell - acts as a barrier - controls what goes in/out

of a cell - made of phospholipids

All cells have these parts…..

• Cytoplasm – jelly like part of cell

All cells have these parts…..

• Organelles – parts inside the cell that carry out certain processes

All cells have these parts…..• Genetic Material – DNA (Deoxyribonucleic Acid)

- contains information needed to make new cells and new organisms

- in some cells, the DNA is contained inside a NUCLEUS

(brain of the cell)

2 Types of Cells…..

• Prokaryotic – cell with NO nucleus

• Eukaryotic – cells do have a nucleus

2 Types of Cells…..

• Prokaryotic –

• Most common are Bacteria (Bacterium)

2 Types of Cells…..

• Prokaryotic –

• 2nd most common are Archae

2 Types of Cells…..• Eukaryotic – Largest cells

- Still microscopic - ~ 10x larger than bacterial cells - Have a nucleus (brain of the cell)

Section 2

• Eukaryotic cells – Animal cells and plant cells are the most common

Animal Cell Plant Cell

Eukaryotic Cells…..• Cell Wall – rigid structure that gives

support and shape- found in plants and algae- made of cellulose (complex

sugar)- Fungus also have cell walls, but

they are made out of chitin- Bacteria and Archae also have cell walls, but are different

Eukaryotic Cells…..

• Cell Membrane – all cells have this - protective barrier - separates from environment

Eukaryotic Cells…..• Cytoskeleton – web of proteins in the

cytoplasm - acts as a muscle and a skeleton - made of 3 types of proteins

Eukaryotic Cells…..• Nucleus – in all eukaryotic cells

- contain DNA (genetic material)

Eukaryotic Cells…..• Ribosomes – smallest organelles

- most abundant organelle - NOT membrane bound - make proteins out of AMINO ACIDS 20 different amino acids

Eukaryotic Cells…..

• Endoplasmic Reticulum – a system of folded membranes in which proteins and lipids are made

- internal delivery system in cell- it is either ROUGH or SMOOTH

Eukaryotic Cells…..• Mitochondria

(mitochondrion) –

- power source of the cell

- breaks sugar down into ATP

- needs oxygen

Eukaryotic Cells…..• Chloroplasts – Only in plants/algae

- carries out PHOTOSYNTHESIS** process of using sunlight, carbon dioxide, and water to make sugar and oxygen

- green (chlorophyll)**traps the sunlight

Eukaryotic Cells…..

• Golgi Complex – packages and distributes proteins from E.R.

- pinches off bubble to transport its contents

Eukaryotic Cells…..

• The bubble is called a VESICLE

Eukaryotic Cells…..• Lysosomes – a special vesicle responsible

for digestion - contain digestive enzymes - destroy damaged/worn out organelles

Eukaryotic Cells…..

• Vacuoles – a vesicle in plant/fungus

- aid in digestion

- storage of water *****

Section 3

• The Organization of Living Things –Cells – every living thing is made of cellsTissue- groups of cells working together to do

a jobOrgans – groups of tissues working together

to do a jobOrgan Systems – groups of organs working

together to do jobOrganism – groups of organ systems working

together to do a job

The Organization of Life…..