Mitochondria Structure and Function Cell Respiration

Name______

Mitochondria Structure and Function – Cell Respiration

Both plant and animal cells contain an organelle called a mitochondria. This allows cells to use sugars the animal or plant eats to make ATP. The cells break down sugars, like glucose, into smaller molecules that get combined with oxygen to make energy, carbon dioxide, and water. The complete reaction:

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

Raw Materials Products

Glucose Carbon Dioxide

Oxygen Water

Adenosine Triphosphate

The energy molecule in the cell is called adenosine triphosphate (ATP). When a phosphate molecule (PO4) is broken off, energy is released for use in the cell. This new molecule is called adenosine diphosphate (ADP). Cell respiration is the process of breaking down the carbohydrates the organism consumes in order to replace broken phosphates onto ADP to turn them into energy carrying ATP.

The Structure of the Mitochondria

Mitochondria are double membrane organelles with a smooth outer membrane and an inner membrane that is folded into zig-zag folds called cristae. Color and label the outer membrane red . Color and label the inner membrane pink .

The inner gel like material in the mitochondria is called the matrix. Color and label the matrix blue . The electron transport chain occurs on the inner membrane with embedded proteins. Label these embedded proteins. They are already colored black for you.

Cell Respiration

Cell respiration begins with glycolysis. This breaks one glucose molecule into two molecules of pyruvate. This occurs in the cytoplasm of the cell and produces 2 ATP as well as another energy molecule called NADH. In reality 4 ATP are produced in this step; however, 2 are also used up in the process. This is called a NET GAIN of 2 ATP.

AEROBIC RESPIRATION

Inside of the mitochondria two processes take place. In the presence of oxygen within the mitochondria the pyruvate molecules enter the Krebs Cycle (sometimes called the Citric Acid Cycle). The Krebs Cycle is the central metabolic pathway in all aerobic organisms. The cycle is a series of eight reactions that occur in the mitochondria. These reactions take a two carbon molecule and completely oxidize it to carbon dioxide. In addition, 2 more ATP are produced.

The Electron Transport Chain happens within the membrane of the mitochondria. Electrons from the Krebs Cycle and NADH molecules from glycolysis are used as an energy source to fix loose phosphates onto ADP to make them energy rich ATP. In the process oxygen (O2) molecules are converted into water (H2O). The Electron Transport Chain produces 34 ATP.

1. Cellular respiration begins with a pathway called ______that splits glucose molecules into two molecules of ______.

1. Is the following sentence true or false? Glycolysis releases a great amount of energy. T / F

1. Breaking the phosphate bond in ATP changes the molecule into ______and releases______.

1. What is cellular respiration?

1. Where does glycolysis take place? What does the word glycolysis mean?

1. Where do the Krebs cycle and electron transport take place?

1. If the cell uses 2 ATP molecules at the beginning of glycolysis, how does it end up with a net gain of 2

ATP molecules?

Label the three phases of Cell Respiration in the picture below.

ANAEROBIC RESPIRATION

In the absence of oxygen fermentation takes place. Fermentation is a metabolic process that converts sugar to acids, gases or alcohol. It occurs in yeast and bacteria as alcoholic fermentation, and also in oxygen-starved muscle cells, as in the case of lactic acid fermentation. Fermentation allows glycolysis to continue by using its by-products. This allows the organisms to continue making energy for their cells. This process uses 2 NADH from glycolysis as well as the pyruvate and produces 2 ATP.

8. What is fermentation?

9. How does fermentation allow glycolysis to continue?

10. Because fermentation does not require oxygen, it is said to be ______.

11. What are the two main types of fermentation?

12. What is the total number of ATP molecules formed during aerobic cellular respiration vs anaerobic cell respiration?

13. Is the diagram below representative of aerobic or anaerobic respiration? ______

Chloroplast Structure and Function – Photosynthesis Name______

Plant cells and some algae contain an organelle called a chloroplast. This allows plants to harvest some energy from sunlight, a process known as photosynthesis. Specialized pigments in the chloroplast absorb sunlight and use this energy to combine carbon dioxide and water to make glucose and oxygen. The complete reaction:

6CO2 + 6H2O + sunlight → C6H12O6 + 6O2

Raw Materials Products

Carbon DioxideGlucose

WaterOxygen

Sunlight

In this way, plant cells manufacture glucose and other carbohydrates that they can store for later use. Plants use photosynthesis to create their own food and then use cellular respiration to turn their food into energy (ATP). Photosynthetic cells are found mainly in the leaves of plants and each cell may have thousands of chloroplasts.

1. What type of cells contains chloroplasts? Are they autotrophs or heterotrophs? Why?

1. What are the reactants for photosynthesis?

1. What carbohydrate is produced?

1. What gas is a reactant? ______a product? ______

The Structure of the Chloroplast

Chloroplasts are double membrane organelles with a smooth outer membrane and an inner membrane that is folded into disc-shaped sacs called the thylakoid. Color and label the outer membrane light green . Color and label the inner membrane brown .

Thylakoids contain chlorophyll and other pigments (red, orange, yellow, brown) and are found in stacks called granum (grana, plural.) Color and label the thylakoids dark green , then highlight the entire stack of granum with yellow . These stacks are connected to other stacks by channels called lamellae. Color and label the lamella orange.

Grana are surrounded by a gel-like material called stroma. Color and label the stroma blue.

9. How many membranes does a chloroplast contain?

10. The INDIVIDUAL SACS formed by the inner membrane are called ______and are arranged in ______like stacks of pancakes.

11. What pigment is found inside a thylakoid? What color will it be?

12. Other pigments that trap sunlight are called ______pigments. What colors are these pigments?

13. STACKS of thylakoids are called ______(plural) or GRANUM (singular).

14. Grana are connected to each other by ______

All autotrophs can make their own food in this way, unlike heterotrophs, which much consume food. When you eat a potato, you are eating the carbohydrates that the plant created from sunlight.

Photosystems Labeling *Label the steps that occur in the process shown*

1) ______

2) ______

3) ______

4) ______

5) ______