AP BiologyTests back Chapter 11

Cell Communication

No Distance

Short Distance

Long Distance

Signal Transduction Pathway

1. Messenger

2. Receptor

3. Transduction

4. Secondary Messengers

5. Cell Targets

AP Biology- take out notes and Study guides

Signal Transduction Pathway

Effects of Changes in Pathways

Signal Disruption Pathways

Disruptions

Poison Diabetes

Cell Division Ch. 12

• Cell division- reproduction of cells• Cell cycle- life of cell• Chromosomes- DNA in packed structures• Chromatin- DNA and proteins• Somatic cells- # of chromosomes per body

cell (all except reproductive) • Gametes- reproductive cells (half of the

somatic #)• Sister Chromatids- duplicated chromosome

joined by centromere

• Mitosis- division of genetic material• Cytokinesis- division of cytoplasm• Animals – cleavage furrow• Plants – Cell plate

Phases of Cell Cycle

Cleavage VS Plate

Binary Fission

• Binary Fission- Division in half (prokaryotes)

•Origin of Replication

Cell Cycle Control System

• Cell cycle is regulated by internal and external signals

• Checkpoint- control point where stop and go signals occur• G1

• S• G2

• G0

Cyclin and Cyclin-Dependent Kinases

• Protein kinases are enzymes that activate or inactivate proteins by phosphorylating them

• To be activated the kinase must be attached to a cyclin

• Because these kinases are dependent upon attachment of cyclin they are known as cyclin-dependent kinases or Cdks.

• Cells respond to • “maturation-promoting factors” this is what triggers the cell’s passage past each checkpoint•Growth hormone•Density-dependent inhibition-

Uncontrolled cell growth-