cellular respiration, photosynthesis, enzyme lab quiz

ETC

Water is formed, NADH becomes NAD+, oxidative phosphorylation, cytochrome carriers

What are the three pathways involved in the complete breakdown of glucose to carbon dioxide and water? What reaction is needed to join two of these pathways? What are the substrates and products of this reaction and where does it take place?

1. Glycolysis 2. Citric acid cycle 3. Oxidative phosphorylation Transition reaction is needed to join two of these pathways Substrates : pyruvate acid, coenzyme A, NAD+ Products : NADH, acetyl coenzyme A, CO2 Mitochondria

List at least three controls in this experiment

1. Water temp 2. Outside pressure 3. Volume of peas

Calculate the energy yield of glycolysis and cellular respiration per glucose molecule. Distinguish between substrate-level phosphorylation and oxidative phosphorylation. Where does the energy for oxidative phosphorylation com from?

2 ATP to start glycolysis = 32 net ATP Substrate level phosphorylation yields 4 ATP, oxidative phosphorylation uses ATP synthase to make 32 ATP The energy comes from electrons being transferred from one electron acceptor to another = hydrogen atoms to enter the inner membrane space = all H+ create proton gradient = leave through ATP synthase = as each H+ leaves, ATP molecule is produced

How can the rate of photosynthesis be measured?

By measuring the uptake of CO2, measuring the production of O2, measuring the production of carbohydrates, measuring the increase in dry mass

During aerobic respiration, glucose is broken down to form several end products. Which end products contain the CARBON atoms from glucose? The HYDROGEN atoms form glucose? The OXYGEN atoms from glucose? The ENERGY stored in the glucose molecules?

Carbon dioxide = carbon Water = hydrogen BOTH carbon dioxide and water = oxygen ATP = energy

Krebs cycle

Carbon dioxide is given off, FAD becomes FADH2

Your teacher has the flu and the only available substitute knows nothing about cellular respiration. You are given the responsibility to provide the substitute teacher with the important background information needed to explain this topic to the next class. Write a short letter, explaining cellular respiration to the substitute teacher.

Cellular respiration is the set of metabolic reactions and processes that take place in the cells of organism to convert biochem energy from nutrients to ATP and then release wastes products. Respiration is one of the key ways a cell gains energy. Cellular respiration is considered and exothermic redox reaction - releases heat.

What is fermentation? What are two types of fermentation? What organisms use fermentation?

Fermentation is an anaerobic process in which energy can be released from glucose even though oxygen is not available. Fermentation occurs in yeast cells and a form of fermentation takes place in bacteria and in muscle cells of animals. The two type of fermentation: alcoholic and lactic acid Obligate anaerobes use fermentation or anaerobic respiration

Which of the two pea types, germinating or non-germinating, consumes the most oxygen? Why?

Germinating peas consume the most oxygen because they are growing and are more active than non-germinating

What was the effect of temperature on pea respiration?

Higher (warmer) temperature makes peas respire at a faster rate

Explain why the water initially moved into the respirometer

It has to do with the need for equal pressure between the environment and the inside of respirometer. When the oxygen was consumed, it created more space for the same time amount of oxygen still present = respirometer has less pressure than outside of vial, water moves to equalize the air pressure

How did the KOH affect the water movement in the respirometer?

KOH absorbs the CO2 given off and the volume changes reflect the change in the volume as CO2 is given off and O2 is taken in

What is the role of KOH in this experiment?

KOH can be used to remove the CO2 provided during cellular respiration, and form solid potassium carbonate

Glycolysis

PGAL, pyruvate

How are respiration and fermentation similar? How are they different?

Respiration : involves Krebs cycle, oxidative phosphorylation, aerobic Fermentation : pyruvate reduced to lactate, pyruvate reduced to alcohol, anaerobic Both : produce ATP

Where in the cells of the leaf do you find air spaces? What is the function of the stoma?

Spongy mesophyll The stoma allows plants to exchange gases needed for photosynthesis

Why do the leaf disks begin to float in the sodium bicarbonate solution but not in the soapy water solution?

The bicarbonate has CO2 so it floated, the soapy water has no CO2 so nothing happened

What will happen if you remove air from the spaces in the plant? How will air return to these spaces?

The leaf will sink If you place the disk in a solution with an alternate source of carbon dioxide (bicarbonate ions) photosynthesis can occur and oxygen accumulates in the air spaces in spongy mesophyll - floating leaf

According to your graph, what happens to the rate of oxygen consumed by germinating peas over time? What does this indicate to you?

The rate of oxygen consumption is increasing over time, meaning that germinating peas consumed more oxygen because it is actively growing

What is the relationship between sodium bicarbonate and photosynthesis rate?

When sodium bicarbonate is added to the water it acts as a carbon source for photosynthesis causing the leaf disks to sink, as photosynthesis proceeds, oxygen is released from the leaf causing it to float