A Cell Review

Brought to you by your local expert:

Mr. Hachtman

The Animal Cell

Cell Membrane

• Thin, flexible barrier surrounding the cell

• Function: Controls what goes into and out of the cell

• Composition: – 2 layers (bilayer) of lipids– Also consists of proteins and carbohydrates

• Analogy: Security at a football game

Cytoplasm

• The “gooey stuff” inside the cell membrane

• “Bathes” the organelles

• Analogy: Swimming pool holding a bunch of kids (green water!)

What exactly is an organelle?

• An organelle is defined as a part of a cell that performs important cellular functions

• Types of organelles found in animals:– Nucleus, Endoplasmic Reticulum,

Mitochondria, Ribosomes, Vacuoles, Lysosomes, Centrioles, and Golgi Apparatus

• Number of a certain type of organelle within a single cell can vary greatly

Organelles: The Nucleus• Contains chromosomes (DNA)

- DNA codes for protein- Making proteins = one of the largest jobs of the cell

• Function: Control center of the cell (controls cellular processes)

• Surrounded by a nuclear envelope: Controls what goes into and out of nucleus (Nuclear pores)

• Consists of 2 membranes

• Contains nucleolus - Involved in making ribosomes

• Nucleoplasm - Gooey sap inside the nucleus

Endoplasmic ReticulumFunction: Assembles and transports components of the cell membrane

Two types:

1) Rough ER

- Contains ribosomes

- Modify proteins

2) Smooth ER

- Lack ribosomes

- Synthesize lipids

Ribosomes

• Function: Site where proteins are assembled

DNA -> RNA -> Protein

• Two Types– Attached ribosomes: On the ER– Free ribosomes: Floating in the cytoplasm

Mitochondria - Think of Mr. H• Function: Produce

energy for the cell

• Appearance: Two separate membranes– Outer membrane– Inner membrane -

Highly folded

• Cristae: Area inside of mitochondria

Cellular respiration occurs in mitochondria: Glucose -> Energy

Golgi Appartus

• Function: Package and ship proteins from the ribosomes

• Analogy: UPS

• Attach carbohydrates and lipids to proteins

Vacuoles and Lysosomes• Vacuole

– Function: Stores food, water, and waste for the cell• Analogy: Toilet that you forget to flush

• Lysosome– Function: Gets rid of waste

• Analogy: Toilet that is flushed

– Contains enzymes– “Suicide Sacs” - Destroys organelles that are too old

and also destroys cell when too old

The Plant Cell

Three differences between plant and animal cells

• Plant cells have:

– Chloroplasts (and other plastids)– Cell wall– Large central vacuole (animals have many

small vacuoles)

Chloroplasts• Involved in Photosynthesis

• Turn sunlight into glucose

• Composition:

• 2 membranes

• Grana contain chlorophyll (green pigment in plant that absorbs sunlight)

Cell Wall

• Found in plants, algae, fungi, and bacteria

• Lies outside the cell membrane

• Function: Provides support and protection for plant cell

• Composition: Made of cellulose (carbohydrate) and proteins

Eukaryotic vs Prokaryotic• True Nucleus

• Examples:

• Plants, Animals, Fungus, Protists

• No True nucleus

• Examples:

• Bacteria

The Meaning of Words

Kary: Nucleus

Eu: True

Pro: Without