Cell Structure & Function

Cell (Plasma) Membrane

- Separates cell from its environment

- Contains phospholipids, proteins, steroids, etc.

Also contains cytosol (intracellular fluid) of the cytoplasm.

Cytoplasm

- Supports cell structure

- Houses organelles

- Contains cytosol

Nucleus

- Coordinates metabolism

- Houses and protects cell DNA

Nucleolus

- Synthesizes rRNA

- assembles large/small ribosomal subunits

Nuclear envelope

- Acts as a barrier separating nucleus from the cytoplasm, in order to protect the cell's genetic material.

Chromatin

- Compact long strands of DNA to fit within nucleus

Centrosome

- The site where microtubules begin to grow.

- Functions as the Main Microtubule Organizing Center.

Centriole

- Each cell contains two centrioles in the cytoplasm.

- Centriole is composed of a microtubule triplet.

- Function is helping movement of chromosomes during cell division.

Ribosome

- RNA and proteins

- Function is protein synthesis

Rough Endoplasmic Reticulum (RER)

- Modifies and packages newly synthesized proteins

Smooth Endoplasmic Reticulum (SER)

- Synthesizes lipids and carbohydrates

Golgi complex

- Processes, modifies, and packages proteins and lipids for transport

Vesicles

- Membrane-bound sacs

- Transports molecules to various locations within or outside the cell.

Mitochondrion

- "powerhouse" of the cell

- Generate majority (~95%) of ATP required by the cell.