1-3 Notes – Cells & Energy Chapter 1, Lesson 3

Cellular Respiration Cellular respiration transforms stored energy in food molecules into usable energy in molecules called ATP (adenosine triphosphate). Takes place in BOTH plants and animals.

Cellular Respiration Step 1 is called glycolysis. Takes place in the cytoplasm A glucose molecule is broken down using energy Two smaller molecules and electrons are released

Cellular Respiration Step 2 Takes place in the mitochondria. Smaller molecules break down. More electrons are released.

Cellular Respiration Step 3 Takes place in the mitochondria. Requires oxygen. ATP is produced. Water is released.

Cellular Respiration C6H12O6 + 6O2 → ATP + 6H2O + 6CO2 glucose + oxygen → energy + water + carbon dioxide Energy is either transported to other parts of the cell wherever it is needed or released as heat. Carbon dioxide is released from the cell.

Fermentation Occurs in cytoplasm only. Does not use oxygen. Produces fewer ATP molecules compared to cellular respiration. 2 types: lactic acid and alcohol.

Fermentation Lactic acid fermentation When our muscle cells run out of oxygen, they can use this to still produce energy. It uses glucose and produces lactic acid and carbon dioxide. Lactic acid fermentation is used in the production of cheese and yogurt.

Fermentation Alcohol fermentation One-celled fungi called yeast use this to produce energy. Uses glucose and produces ethanol and carbon dioxide. Produces fewer ATP molecules than lactic acid fermentation. Used in baking bread.

Photosynthesis Some organisms use photosynthesis to make food using a light source.

Photosynthesis Objects reflect some colors and absorb others. Chloroplasts in plants contain the pigment chlorophyll that reflects green light.

Photosynthesis Light energy is absorbed by chlorophyll and other pigments in the chloroplasts. In photosynthesis, light energy, water, and carbon dioxide are used to make sugar. Oxygen is released into the atmosphere during photosynthesis.

Photosynthesis

Photosynthesis

6CO2 + 6H2O + sunlight → C6H12O6 + 6O2 Photosynthesis 6CO2 + 6H2O + sunlight → C6H12O6 + 6O2 carbon + water + energy → glucose +oxygen dioxide The energy from the glucose is either used immediately, or stored for later use. The oxygen is released through the leaves.

During the spring and summer leaves serve as factories where most of the foods necessary for the tree's growth are manufactured. The process, known as photosynthesis; takes place in the leaf in numerous cells containing chlorophyll, which gives the leaf its green color. Along with the green pigment are yellow to orange pigments; carotenes and xanthophyll, however most of the year these colors are masked by great amounts of chlorophyll. In autumn, because of the changes in daylight hours and changes in temperature the leaves stop photosynthesizing and hence the chlorophyll breaks down. The green color disappears, and the yellow and orange colors become visible. At the same time, other chemical changes may occur, which form additional colors through the development of red anthocyanin pigments. Eventually the tree sheds the leaves to save nutrients and prevent loss of water, the leaves then rot and return to the soil as organic matter.

Glycolysis is part of what process? A cellular respiration 1.3 Cells and Energy Glycolysis is part of what process? A cellular respiration B lactic acid fermentation C alcohol fermentation D photosynthesis

What makes leaves appear green? A water B carbon dioxide C glucose 1.3 Cells and Energy What makes leaves appear green? A water B carbon dioxide C glucose D chlorophyll

Where does photosynthesis occur? A cytoplasm B mitochondria 1.3 Cells and Energy Where does photosynthesis occur? A cytoplasm B mitochondria C chloroplasts D muscles

What is required for fermentation? A oxygen B glucose C lactic acid D carbon dioxide