Photosynthesis Questions

The type of tightly packed plant cells that are able to photosynthesize.

Palisade parenchyma

When guard cells do this, they close.

Guard cells close when they loose water.

Guard cells form an opening in the lower epidermis called what?

Stomates

Does a photosystem contain more than one pigment?

Yes, it contains molecules of various pigments such as, carotenoids, chlorophyl a and b.

What is photolysis?

When water is split in photosystem II to replace electrons.

What happens at the p6f complex in photosystem II?

H+ ions are pumped into the thylacoid and they diffuse out through ATP Synthase to form ATP.

What are plastoquinone and plastocyanin?

Proteins in the thylacoid membrane that transfer the electrons.

What do plants do when there is not enough NADP molecules to accept electron?

They perform Cyclic photophosphorylation where the electrons excited at p700 (photosystem I) return to p700 after transferring from several membrane proteins.

What is the enzyme that fixes carbon from CO2 to form PGA?

Rubisco or RuBP carboxylase

When PGA is converted to G3P which goes on to form organic molecules and more RuBP, it is the ________pathway?

C3 pathway

The pathway where plants first incorporate CO2 with PEP to form oxaloacetate and the glucose. Why do plants use this pathway?

C4 Pathway (Hot, dry climates Take advantage of intense sunlight Ex. Sugar cane and corn)

Where does the Calvin cycle occur?

Stroma

The waxy covering of leaves

Cuticle

Why are plants green?

Green is the light they reflect.

What is an absorption spectrum?

A graph showing wavelength vs absorbance of a particular substance A graph showing wavelength vs absorbance of a particular substance. From the data it can be determined what specific wavelength is absorbed.

What is a “blank” needed to obtain accurate readings with a spectrophotometer?

A Blank has all of the buffer, dilutants, and or solvents used in a sample and not what is being tested.

What is an Rf value for a pigment?

The reference front or the distance the pigment migrated divided by the distance the solvent front moved.

Why was a flask of water places between the samples and the lamp in the lab?

To act as a heat sink….so heat would not have an effect on the results.

According to the lab, what would it indicate if the O.D. of a tube was .67 at time “O” and .65 at time “5”

It would indicate that no photosynthesis occurred in the sample.

What is TLC?

Thin layer chromotography

Respiration Questions

In Glycolysis, Glucose in broken down into what?

2 Pyruvic acid molecules (pyruvate)

Which steps of respiration form ATP?

Glycolysis Kreb’s cycle Electron Transport Chain (Oxidative phosphorylation)

Where does glycolysis occur?

The cytoplasm

Is glycolysis anaerobic?

Yes, glycolysis does not require oxygen Yes, glycolysis does not require oxygen. This occurs in both aerobic and anaerobic respiration.

What happens is glycolysis continues anaerobically?

Only a net of 2 ATPs are formed and this is called fermentation.

During respiration as organic molecules are broken down in to smaller carbon molecules, what happens to the carbon?

The carbon is released as Carbon dioxide.

What is produced with one turn of the Kreb;s cycle What is produced with one turn of the Kreb;s cycle? (one turn referring to one of the acetyl CoA molecules)

1 ATP molecule 3 NADH 1 FADH2 (double this to represent both acetyl CoAs)

Where does the electron transport chain take place?

In the cristae membrane.

What are the protein electron carrier molecules involved in respiration?

NAD+  NADH FAD FADH2

The hydrogens removed from glucose and picked up by the “shuttles” actually become this in the electron transport chain?

H2  2H+ + 2 e- Hydrogen ions and electrons

What happens to the H+ ions? What happens to the e-?

The H+ ions are used to form ATP by way of Chemiosmosis. The e- combine H+ and oxygen to make water.

This is the 6 carbon intermediate in the Kreb’s Cycle.

Citric Acid

These are the types of proteins that make up most of the Electron Transport chain.

Cytochromes

What happens to lactic acid that is formed in anaerobic respiration in some bacteria and your muscle cells?

It is converted by the liver into Carbon dioxide and water.

Why was it neccessary to understand the gas laws for the respirometer lab?

Pressure and temperature can effect volume of a gas.