What is a cell A cell is the

CELL THEORY 1. The basic unit of life is the cell. (Hooke) • In

CELL THEORY 2. All living things are made of 1 or more cells. •

CELL THEORY 3. All cells divide & come from old cells. (Virchow) Virchow

The different shapes of cells reflect their different functions. • The long extensions that

What limits cell size? • Small cells can exchange substances(oxygen, nutrients, and carbon dioxide)

There are 2 kinds of cells: • Eukaryotes – Have a nucleus • •

Prokaryotic Cells • No ____________________ • Examples: Bacteria • Prokaryotic cells include the following

Eukaryotic Cells • • Have ___________ Have ________ Larger than Prokaryotic Cells Examples: –

Cells have specialized structures to carry out functions. These are called organelles.

Cell Organelles: • Nucleus – command center of the cell. Contains the cell’s genetic

Cell Organelles: • Endoplasmic Recticulum (ER) – makes lipids, proteins and other materials that

Cell Organelles: • Ribosomes – small particles of RNA and protein found throughout the

Cell Organelles: • Golgi Apparatus– modifies, sorts and packages the proteins that come from

Cell Organelles • Vacuoles – saclike structures used to store materials such as water,

Cell Organelles • Mitochondria – converts food into energy that the cell can use.

Cell Organelles • Cell membrane – regulates what enters and leaves the cell and

Cell Organelles • Nuclear membranesurrounds the nucleus and allows material to move in and

Cell Organelles: • Chloroplasts – ONLY FOUND IN PLANT CELLS - captures energy from

• Peroxisomes—absorb nutrients, digest fatty acids, and alcohol -breakdown toxic hydrogen peroxide to

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What is a cell? A cell is the smallest unit of life. The cell theory states: ● All living things are made up of cells ● Cells are the basic units of structure and function in living things ● New cells are produced from existing cells

CELL THEORY 1. The basic unit of life is the cell. (Hooke) • In 1665, an English scientist named Robert Hooke made an improved microscope and viewed thin slices of cork viewing plant cell walls • Hooke named what he saw "cells"

CELL THEORY 2. All living things are made of 1 or more cells. • Matthias Schleiden (botanist studying plants) • Theodore Schwann (zoologist studying animals) stated that all living things were made of cells Schwann Schleiden

CELL THEORY 3. All cells divide & come from old cells. (Virchow) Virchow

The different shapes of cells reflect their different functions. • The long extensions that reach out in various directions from the nerve cell allows the cell to send and receive nerve impulses(messages) • The flat, plate-like shape of skin cells suits their function of covering and protecting the surface of the body.

What limits cell size? • Small cells can exchange substances(oxygen, nutrients, and carbon dioxide) more readily than larger cells because small objects have a higher surface area to volume ratio. • So, the cells divide!

There are 2 kinds of cells: • Eukaryotes – Have a nucleus • • Examples of prokaryotes are eukaryotes are bacteria plants, animals, fungus, and protists • More complicated • Prokaryotes – Do NOT have a nucleus • Smaller than eukaryotes • Less complicated

Prokaryotic Cells • No ____________________ • Examples: Bacteria • Prokaryotic cells include the following features: – Smaller in size – DNA in a nucleoid region – Cell membrane – Ribosomes – Cell wall of peptidoglycan

Eukaryotic Cells • • Have ___________ Have ________ Larger than Prokaryotic Cells Examples: – animal cells, – plant cells, – fungi cells and – protist cells

Cells have specialized structures to carry out functions. These are called organelles.

Cell Organelles: • Nucleus – command center of the cell. Contains the cell’s genetic material in the form of DNA. ONLY FOUND IN EUKARYOTES • Cytoplasm – the “gel” material inside the cell membrane but not in the nucleus. The organelles live inside the cytoplasm.

Cell Organelles: • Endoplasmic Recticulum (ER) – makes lipids, proteins and other materials that are exported (taken out) of the cell. • Rough ER – part of the ER that makes proteins. -Called “rough” because ribosomes are attached to the surface and makes it look bumpy. • Smooth ER – part of the ER that makes lipids and contains enzymes. Also plays a role in the detoxification of drugs. Ex. ) Liver cells play a key role in detoxifying drugs, so they contain large amounts of Smooth ER. -Called “smooth” because ribosomes are not attached to the surface.

Cell Organelles: • Ribosomes – small particles of RNA and protein found throughout the cytoplasm. They produce proteins by following instructions that come from the nucleus.

Cell Organelles: • Golgi Apparatus– modifies, sorts and packages the proteins that come from the Rough ER and either stores them or ships them out of the cell. • Lysosome – removes waste from the cell.

Cell Organelles • Vacuoles – saclike structures used to store materials such as water, salts, proteins, and carbohydrates.

Cell Organelles • Mitochondria – converts food into energy that the cell can use. They are the power centers of the cell. • Cytoskeleton – supports the cell and helps to maintain the shape.

Cell Organelles • Cell membrane – regulates what enters and leaves the cell and also provides protection and support. • Centriole-located near the nucleus and helps organize cell division. Not found in plant cells.

Cell Organelles • Nuclear membranesurrounds the nucleus and allows material to move in and out of the nucleus. • Nucleolus- within the nucleus, where the assembly (making) of ribosomes begin.

Cell Organelles: • Chloroplasts – ONLY FOUND IN PLANT CELLS - captures energy from sunlight and converts it into chemical energy in plant cells. • Cell Wall – ONLY FOUND IN PLANT CELLS - provides support and protection for the plant cell.

• Peroxisomes—absorb nutrients, digest fatty acids, and alcohol -breakdown toxic hydrogen peroxide to water