Bioenergetics

What are the different energy molecules in the cell? Describe the energy storage capacity of each and relate this to their function in living organisms.

ATP - stores small amounts of energy that is easily accessible to all

parts of the cell; used to run all cellular activities.

Glucose - stores larger amounts of energy that is more difficult to access; converted into ATP when energy is needed.

What are the three parts of an ATP molecule?

adenine, ribose, and phosphate group

Energy is released from an ATP molecule when:

A phosphate group is removed

How do heterotrophs and autotrophs differ in the way they obtain energy?

Autotrophs make their own food by using sunlight or inorganic molecules, hetetrotrops consume other organisms.

Which organelle is involved in photosynthesis? List and describe the parts of this organelle.

Chloroplasts are the plastids involved in photosynthesis, they carry out photosynthesis in eukaryotic cells, and some prokaryotes. This is without chloroplasts. The light-dependent reactions occur in the thylakoid membrane and stack of thylakoids are called grana. The reactions occur in the stroma.

2. Explain what happens to energy during photosynthesis. In what form does it enter photosynthesis? In what form does it exist during photosynthesis? In what form does it leave photosynthesis? How is this related to the overall goal of photosynthesis?

In photosynthesis, energy is light-energy from the sun, which is turned into reactions converted to chemical energy. These are stored as glucose. Photosynthesis converts light energy into a form usable by living organisms.

Plants absorb energy with light-absorbing molecules called:

Pigments

What is the primary pigment involved in photosynthesis? Why do plants also contain accessory pigment?

Chlolorphyll is the green pigment that cannot absorb light from the electromagnetic spectrum. Accessory pigments absorb light wavelengths

A student exposed one plant to only red light and another to only green light. Which should grow better and why?

The plant under the red light because the chlorophyll reflects green light, which prevents the plant from abosirng the light and stunting its growth.

Write the basic equation for photosynthesis using the names of the molecules involved. Identify the products and reactants. Is light a product or reactant? If not, what does it supply to the equation?

Water+Carbon Dioxide→Sugar + Oxygen

Reactants - water, carbon dioxide & Products - sugar, oxygen; light supplies energy for the reaction not the prodcut.

A student is collecting gas being given off by a plant in direct sunlight. The gas is most likely:

Oxygen

What are the products and reactants of cellular respiration? Where does the reaction take place in cells?

Reactants are sugar and oxygen and cellular respiration takes place in the mitochondria.

How is energy transformed during cellular respiration? In what form does it enter cellular respiration? In what form does it leave cellular respiration? How is this related to the overall goal of cellular respiration?

Energy enters as stored energy in glucose that leaves cellular respiration as ATP. The goal is to provide the energy used by the cell as glucose to ATP.

What is a calorie? Briefly explain how cells use a high-calorie molecule such as glucose.

A measure of energy that cells can use high-calorie molecules for energy storage.

Compare and contrast photosynthesis and cellular respiration in terms of product, reactant, and energy transformations in each.

Photosynthesis: Products: Carbon Dioxide, Water, Light energy. Reactants: Sugar, Oxygen; converts light energy into chemical energy.

Cellular respiration: Products: Water, Carbon dioxide, ATP; Reactants: Sugar, oxygen; converts stored chemical energy into usable energy.

Why are photosynthesis and cellular respiration considered opposite reactions?

The products of one are the reactants of the other.

Compare and contrast fermentation and cellular respiration in terms of product, reactant, and energy transformations involved.

They both start with sugar, but cellular respiration requires oxygen. It producesMcarbon dioxide, water, and energy. Fermentation produces less ATP.

Because fermentation takes place in the absence of oxygen, it is said to be

Anaerobic

In what circumstances is fermentation a better option than cellular respiration and vice versa?

CellularMrespiration would be best because it produces more energy. Fermentation is better without oxygen because cellular respiration cannot take place.

Certain bacteria thrive in conditions that lack oxygen. What does that fact indicate about the way they obtain energy?

They use fermentation, and cellular respiration needs oxygen.

In certain cases, regular exercise causes an increase in the number of mitochondria in muscle cells. How might that situation improve an individual’s ability to perform energy-requiring activities?

Cellular respiration happens inside the mitochondria, so it would increase the rate of energy production.

Why must plants contain mitochondria, despite the fact that they can turn light energy into chemical

energy?

Plants create energy in the form of glucose that needs to be converted into ATP.

The process by which plants use sunlight to create food:

Photosynthesis

Organisms that can form food from sunlight or chemicals

Autotrophs

Organisms that must consume food for their energy:

Heterotrophs

Pigment used by plant cells to capture light energy

Chlorophyll

Organelles found in plants that carry out photosynthesis:

Chloropasts

Area within the chloroplasts where the light-dependent reaction takes place:

Thylakoids

Area within the chloroplast where the Calvin cycle takes place:

Stroma

Used in the light dependent reaction, it is split to form hydrogen and oxygen:

Water

Required in the Calvin cycle to provide the raw ingredients to make glucose:

Carbon Dioxide

Organelles that use glucose to harvest energy for the cell:

Mitochondria

This molecule is released as a product during the light dependent reactions:

Oxygen

A product of photosynthesis; energy storage molecule

Glucose

During this reaction, carbon dioxide is used to create glucose:

Calvin Cycle

During this reaction, ATP is produced to power the calvin cycle:

Carbon Dioxide and water

This energy storing molecule contains 3 phosphates, adenosine, and ribose:

ATP

Glucose forms chains for long term energy storage; these substances are called:

Glycogen

The organelle associated with cellular respiration is the_

Mitochondria

Cellular respiration is the process by which cells convert __ into energ

Glucose

The chemical equation for cellular respiration is:

Glucose + Oxygen ---> Carbon Dioxide + Water + ATP

The function of cellular respiration is to produce _, the cell's energy currency.

ATP

Anaerobic respiration is a type of cellular respiration that does not require _

Oxygen

During glycolysis, a molecule of glucose is broken down into two molecules o

Pyruvate

__is a type of anaerobic respiration that occurs when there is not enough oxygen availa

Fermentation

Yeasts produce this product during fermentation

Ethanol

Humans undergo ___ fermentation when muscles don’t have enough oxygen.

Lactic Acid

The first stage of cellular respiration is

Glycolysis

The second stage of cellular respiration is the __ cycle.

Krebs

The third stage of cellular respiration is the __ transport chain.

Electron

The majority of ATP is produced in the third stage, through __ phosphorylation

Oxidative

ATP __ is a protein that uses the proton gradient in the ETC to make ATP.

Synthase

Is fermentation an aerobic or anaerobic process? What does that mean?

Anaerobic process, because it doesn’t require oxygen.

What is the starting molecule for both lactic acid and alcohol fermentation?

Glucose

What is the net gain of ATP from fermentation for one molecule of glucose?

2 ATP per glucose

What is the final product of lactic acid fermentation?

Lactic Acid

In which human cells does this process occur during strenuous exercise?

Muscle cells

The molecule __ from glycolysis is converted directly into lactic acid.

Glucose

What are the two final products of alcohol fermentation?

Ethanol and Carbon Dioxide

What common microorganism performs this type of fermentation?

Bacteria (e.g.Lactobacilius)

Which product of alcohol fermentation is responsible for making bread dough rise?

CO2 production

In alcohol fermentation, pyruvic acid is converted directly into ethanol in a single step.

False

What is one key similarity between lactic acid and alcohol fermentation (besides both being anaerobic)?

They both have the same starting molecule, glucose.