Biology 152

Cells and Molecular Biology

Exam 3 Study Sheet

Chapter 8: Traffic across membranes:

Explain why molecules like CO₂ and O₂ can pass through the lipid bilayer, but molecules like glucose require transport proteins

Define a transport protein, tell how it works, and give an example

Explain the difference between active transport and passive transport

Explain why osmosis is a special case of diffusion

Define hypertonic, hypotonic, and isotonic

Given a set of solutions, identify which pairs are hypertonic, which are isotonic, and which are hypotonic.

Describe the different strategies used by cells with cell wall and those without cell walls to regulate water balance.

Explain why you can take lettuce celery that is limp and cause it to become crisp again by placing it in cold water.

Explain and give a specific example of facilitated diffusion

Explain the difference between a protein channel and a gated protein channel

Draw an diagram of a sodium-potassium pump and explain how it works, and why it requires ATP

Explain how a proton pump in a mitochondrial or chloroplast membrane differs from a sodium-potassium pump.

Give a specific example of a cotransport system and explain how it works

Define exocytosis and endocytosis

Explain the differences among three types of endocytosis: phagocytosis, pinocytosis, and receptor mediated endocytosis

Review the Self Quiz questions 4-18

Chapter 9: Cellular Respiration

Use the ATP-ADP cycle to illustrate how cells recycle chemical molecules

Show how exergonic reactions such as glucose hydrolysis are linked to endergonic reactions such as phosphorylation of ADP

Distinguish among glycolysis, Krebs' cycle, and electron transport

Given an unlabeled diagram of glycolysis or Krebs' cycle, show where energy is added to the process by phosphate transfer, where ADP is phosphorylated to yield ATP, and where energy is recovered by reduction of NAD or FAD

Calculate the net energy yield (in ATP units) from glycolysis and Krebs' cycle

Explain the importance of each of the following intermediates in cellular respiration: glucose, fructose-1,6-bisphosphate, glyceraldehyde-3-phosphate, phosphoenolpyruvate, pyruvate, acetyl CoA, oxaloacetate, citrate, succinyl CoA, malate.

On an unlabled diagram of the mitochondrial electron transport chain, show where NADH and FADH are reduced, where protons are pumped, and where O₂ is reduced

Explain how chemiosmosis is used to provide the energy to phosphorylate ADP to ATP

Explain, using a specific example, how fermentation can be used to remove pyruvate from cells

Show how fats can be broken down to enter glycolysis and Krebs' cycle

Using alpha-ketoglutarate as an example, show how Krebs' cycle can be used to supply the cell with the building blocks of amino acids.

Study self-quiz questions 1-15.

Chapter 9: Photosynthesis

Define: autotroph, heterotroph, chlorophyll, stomata

Explain the differences between the light-dependent reactions and the light-independent reactions (Calvin cycle) of photosynthesis

Diagram the structure of a typical photosystem.

Explain the roles of antenna pigments and reaction center chlorophyll in the light dependent reactions

Explain how the roles of chlorophyll a and chlorophyll b differ in the photosynthetic reaction center

Explain how cyclic photophosphorylation differs from noncyclic photophosphorylation

Explain how the photosynthetic electron transport chain is similar to and different from the mitochondrial electron transport chain

Describe the function of rubisco

Compare the energy required make a molecule of glucose (in ATP units) with that derived from a molecule of glucose in respiration.

Give a plausible explanation of why rubisco can catalyze photorespiration

Describe one of the two ways that plants growing in warm areas can minimize photorespiration

Study all of the self-quiz questions at the end of the chapter