Study Guide (2,3,4)

Page 3 Information

Active Transport

Movement from low to high concentration.Requires ENERGY.3 Types of Active Transport:

- Protein PUMPS- Endocytosis (Phagocytosis)- Exocytosis

Protein “Pumps”Movement of molecules from Low concentration into High

concentrations, requiring energy.

Endocytosis or Phagocytosis• Active transport of large particles INTO the cell, by

surrounding them with the cell membrane.

Exocytosis

• Active transport of substances OUT of the cell using the cell membrane.

Cell Cycle• Makes up the life of the

cell• Consists of 3 phases:– Interphase, Mitosis &

Cytokinesis• Interphase is divided into

3 parts (G1, S, G2)• Some cells, like muscle

and nerve, do not pass the G1 phase (G0)

Two types of cell/nucleus division.Mitosis = 2 copies of identical cells, with exact amount of DNA/chromosomes. Growth & Repair of normal body cells (Somatic Cells)

Meiosis = 4 unique gametes (egg/sperm) with ½ the chromosomes as the original cell. Gamete production only!

Cell Differentiation

• Cells have varying shapes and functions depending on activation or shut down of portions of DNA.

• Stem Cells – have not yet had any portion of DNA shut off!

Special Events in Cell Cycle

• Cancer = Cells that have incorrectly copied DNA in S phase. Alters rate of cell division or function of cells produced.

• Apoptosis = programmed cell death.

Enzymes = Proteins that speed up all chemical reactions in living things.

• Substrate = molecule the enzyme alters.

• Active site = region on enzyme that has matching shape of substrate.

• Denature = changing the shape of an enzyme (pH & temp)