Get ready for lab quiz

14 days until AP BIO Final-75 questions-Photo/cellular respiration-Cell communication + cell cycle (Chapters 11-13)-Ecology-Cell-Evolution-Labs-Water and Chemistry of Life

-Colored book CAN be used on FINAL

Monday, May 14th at 8am

AP Biology Exam

Lab Quiz—Photo + Cellular Resp

1. In the cell respiration lab, the role of KOH was___________________

2. In the cell respiration lab, we measured_________________________

3. Oxygen is needed by living organisms to____________________

4. In the chromatography lab, the pigments were found in the spinach leaf were________

5. The reason that pigments had different Rf values is________________

Lab Quiz—Photo + Cellular Resp

1. In the cell respiration lab, the role of KOH was to make CO2 a solid; reduce the volume

2. In the cell respiration lab, we measured the O2 consumed

3. Oxygen is needed by living organisms to collect the electrons in the ETC

4. In the chromatography lab, the pigments were found in the spinach leaf were chlorophyll a, chlorophyll b, xanthophyll, and carotene

5. The reason that pigments had different Rf values is that they have different properties and react differently with the chromatopraphy paper AND have high/low soluability in the solvent

Averages for Lab Report—2 LABS DUE FRI

Averages from Chromatography Lab

Chlorophyll a=0.249

Chlorophyll b=0.370

Xanthophyll=0.446

Carotene=1

OIL RIG

OIL=Oxidized Involves Losing electrons

RIG=Reducing Involves Gaining electrons

Oxidized or Reduced?

NAD + NADH

O2 H2O (cellular respiration)

H2O in photosynthesis

Dispatch

1) How do you think one part of the body communicates with the other over SHORT distances? Over LONG distances?

2) What do you think the jar is representing? Open jar=2 Phosphates (ADP); Closed jar=3 Phosphates (ATP)

Cell Communication

http://video.search.yahoo.com/search/video;_ylt=A0oGdWOXyBFPwhsAQ5V

XNyoA?p=dominoes%20knocking%20over&fr=yfp-t-701&fr2=piv-web

The Cellular “Internet”

Within multicellular organisms, cells must communicate with one another to coordinate their activities

A signal transduction pathway is a series of steps by which a signal on a cell’s surface is converted into a specific cellular response

Signal transduction pathways are very similar in all organisms, even organisms as different as unicellular yeasts and multicellular mammals

Local (Short-Distance) Signaling Cells may communicate by direct contact

Plasmodesmata in plant cells Gap junctions in animal cells

Animal cells can also use cell-cell recognition Membrane-bound surface molecules can interact and

communicate

Local (Short-Distance) Signaling Messenger molecules can also be secreted by the signaling cell Paracrine signaling:

One cell secretes (releases) molecules that act on nearby “target” cells Example: growth factors

Synaptic Signaling: Nerve cells release chemical messengers (neurotransmitters) that

stimulate the target cell

How do you think one part of the body communicates with the other over LONG distances?

Long-Distance Signaling

Endocrine (hormone) signaling Specialized cells

release hormone molecules, which travel (usually by diffusion through cells or through the circulatory system) to target cells elsewhere in the organism

The body needs more of protein X.

DNARNAProtein X

How do we turn on transcription?

Phosphorylation

The protein being phosphorylated GAINS a phosphate

A molecule that is phosphorylated has an increased chemical reactivity; it is primed to do cellular work.

The Three Stages of Cell Signaling

There are 3 stages at the “receiving end” of a cellular conversation:

1. Reception2. Transduction3. Response

Stage 1: Reception The target cell “detects” that there is a signal molecule

coming from outside the cell The signal is detected when it binds to a protein on the cell’s

surface or inside the cell The signal molecule “searches out” specific receptor proteins

The signal molecule is a ligand• It is a molecule that specifically binds to another one (think enzymes!)

Stage 2: Transduction

This stage converts the signal into a form that can bring about a specific cellular response One signal-activated receptor activates another

protein, which activates another molecule, etc., etc.

These act as relay molecules Often the message is transferred using protein

kinases, which transfer phosphate groups from ATP molecules to proteins

Stage 2: Transduction

Stage 3: Response

The signal that was passed through the signal transduction pathway triggers a specific cellular response Examples: enzyme

action, cytoskeleton rearrangement, activation of genes, etc., etc.

Diagram example: transcription of mRNA

The Specificity of Cell Signaling

The particular proteins that a cell possesses determine which signal molecules it will respond to and how it will respond to them

Liver cells and heart cells, for example, do not respond in the same way to epinephrine because they have different collections of proteins

Animation

http://bcs.whfreeman.com/thelifewire/content/chp15/15020.html

1) What is flight or fight?2) What is glycogen?

Word bank: signaling molecule, cell receptor, signal transduction pathway, nuclear signaling, cascade, phosphorylation, ATP, protein, response, nucleus, mRNA, second messenger