The Cell October 6, 2009

Organelles – structures found in eukaryotic cells that act as specialized “organs” for the cell.

1. Cytoplasm A fluid-like substance outside of the nucleus.

Cytoplasm

2. Nucleus 2. Nucleus – the “control center” of the cell. Contains cells’ DNA Surrounded by a nuclear envelope. –Nuclear pores allow material in and out of the nucleus. Contains chromatin –Condenses to chromosomes during cell division Contains a nucleolus –Small, dense region in the center of the nucleus –Where ribosomes are assembled.

Cytoplasm Nucleus Nucleolus Nuclear Envelope

3. Ribosomes Site of protein assembly. Small particles of RNA and protein found throughout the cytoplasm

Cytoplasm Nucleus Nucleolus Nuclear Envelope Ribosomes

4. Endoplasmic Reticulum Two types: a.Rough ER – lined with proteins Involved in protein synthesis b.Smooth ER – No ribosomes present Contain enzymes that perform specialized tasks such as synthesis of lipids and detoxification of drugs

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Ribosomes

5. Golgi Apparatus The “packaging” area of the cell. –Modifies, sorts and packages proteins and other materials from the endoplasmic reticulum for storage in the cell or secretion outside the cell.

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Golgi Apparatus Ribosomes

6. Lysosomes The “clean-up crew” of the cell. Small organelles filled with enzymes that digests lipids, carbohydrates, and proteins in the cell so they can be used. Breakdown organelles that are too old to function correctly

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Golgi Apparatus Lysosome Ribosomes

7. Mitochondria “Power-house” of the cell. Convert chemical energy stored in food into compounds that are able to be used by the cell.

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Golgi Apparatus Lysosome Mitochondria Ribosomes

8. Cytoskeleton Support structure and transportation system of the cell. Filaments help the cell maintain its shape and aid in movement. Contains 2 primary protein filaments – microfilaments and microtubules

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Golgi Apparatus Lysosome Mitochondria Cytoskeleton Ribosomes

9. Cell Membrane The “entry gate” of the cell. Controls what enters and exits the cell and also provides protection and support. Consists of a lipid bilayer.

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Golgi Apparatus Lysosome Mitochondria Cytoskeleton Cell Membrane Ribosomes

10. Centriole – Aids in cell division.

11. Flagella Aids in movement of a cell. Sperm Cell Bacteria

Cytoplasm Nucleus Nucleolus Nuclear Envelope RER SER Golgi Apparatus Lysosome Mitochondria Cytoskeleton Cell Membrane Ribosomes Flagella

The Plant Cell

1. Cell Wall Found only in plants –Provides protection and support for the cell. –Lies outside the cell membrane.

Cell Wall

2. Vacuoles “Storage sac” of the cell. Found primarily in plant cells and small single-celled organisms. Function to store materials such as water, salts, proteins and carbohydrates.

Cell Wall Chloroplasts

3. Chloroplasts Solar energy supply Found only in plants Capture the energy from sunlight and convert it into chemical energy in the process called photosynthesis

Cell Wall Vacuole Chloroplasts