Mr. Gaccione

• Power point presentation of the cell

•Cell Structure & Function

THE CELL THEORY

• The cell is the basic unit of all living things.

• All organisms are composed of one or more cells

• All cells come from pre-existing cells

Cell discovery• Robert Hooke - discovered cells while looking at cork cells. mid-1600s

• Anton von Leeuwenhoek - discovered life while looking at pond water. mid-1600s

• Mattias Schwann - all animals consists of cells.1830s

• Theodore Schleiden - all plants consists of cells. 1830s

Cells have many different parts called organelles that work together

to keep it alive.3 main parts of the cell3 main parts of the cell:

1. Nucleus1. Nucleus – The brain. The nucleus is the control center of the cell. It is the largest organelle in the cell and it contains

the nucleolus and DNA.

2. Cell membrane2. Cell membrane –Gives the cell shape & hold the cytoplasm.

3. Cytoplasm3. Cytoplasm – Jellylike material that makes up most of the cell. Most chemical reaction in the cell take place here.

All organelles are suspended in the cytoplasm.

Three main parts of a cellCYTOPLASM

NUCLEUS

CELL

MEMBRANE

Other organelles of the cell:Nuclear membraneNuclear membrane – • surrounds the nucleus and separates

it from the rest of the cell.• allows materials in & out of the

nucleus.

•Has small openings in the nuclear membrane called Pores….

Analogies of a nuclear membrane would be a window screen and pores of the skin.

QuickTime™ and a decompressor

are needed to see this picture.

ANALOGIES

NucleolusNucleolus – found within the nucleus.

produces ribosomes.

Chromosomes Chromosomes – Carries information that determines what traits a living thing will have. Found within

the nucleus. DNA (Deoxyribonucleic Acid) contains all the

information for cells to live, perform their functions and reproduce.

Cell membraneThe fluid mosaic model describes the

structure of the plasma membrane.

Fluid = flexibility. Mosaic = many parts.

The membrane is seen as a bilayer of phospholipids in which protein molecules are

embedded.

RibosomesRibosomes Found in the cytoplasm, but most are

attached to the endoplasmic reticulum.

Ribosomes produce proteins.

Ribosomes• While attached to the ER,

ribosomes produce proteins that are needed in the cell and exported elsewhere in the body.

Endoplasmic reticulum – A network of membranes throughout the

cytoplasm.

Ribosomes are little factories that send proteins to the ER

Transports materials in & outside the cell. Considered smooth or rough.

Mitochondria Mitochondria – organelle that converts food molecules

into energy(ATP). Powerhouse of the cell.

The process of cellular _________ occurs here.

respiration

Mitochondria(continue)

• Every type of cell has a different

amount of mitochondria.

• There are more mitochondria in cells that have to perform lots of work, for example - your leg muscle cells, heart muscle cells etc.

Vacuole Vacuole – Liquid-filled space that stores food,

water, and wastes.Larger in plant cells.

Gives support - turgor pressure..

Vacuole under the microscope

Centrioles Centrioles – Helps with cell reproduction.

Always found in pairs next to the nucleus

Centrioles align spindle fibers

Chloroplasts Chloroplasts Found only in plant cells. Contains green pigment (chlorophyll), that traps energy from the sun. Photosynthesis occurs here.

Cell wall Cell wall Found only in plant cells.

A thick covering outside the cell membrane.

Cell wall• protects the cellular

contents

• gives support to the plant structure

• provides a porous medium for the circulation  and distribution of water, minerals, and other small nutrient molecules

• The cell wall is formed from fibrils of cellulose molecules

Lysosomes-(lysol) -contains digestive enzymes break down materials, such as worn out cells and bacteria.

Golgi bodies – Receives proteins from rough ER.

Packages and delivers proteins to needed areas.

Cytoskeleton - made of microtubules, that give

structure and support to the cell.

-found within the cytoplasm.

Animal cell vs. Plant cellcentrioles cell wall, chloroplast

& larger vacuole

cytoskeleton

Differences between Eukaryotic & Prokaryotic

cells

1. Eukaryotic cells have many organelles Prokaryotic lack organelles no nucleus

2 Eukaryotic are much larger than Prokaryotic cells

3 Examples of Eukaryotic cells - animal & plant cells Examples of Prokaryotic cells - bacterial cells

smooth ER / mitochondria / nucleus / nucleolus / cell membrane centriole / golgi appartatus / cytoskeleton

lysosomes / ribosomes / rough ER / cytoplasm

mitochondria

golgi appartatus

nucleolus

nucleus

centriole

cytoskeleton

cytoplasm

ribosomes

cell membrane

smooth ER

rough ER

lysosomes