Cells Capture and Release EnergyChapter 2.2C

Warm-up—COPY!!!1. The Sun provides much of the energy needed

for ALL living things. How?2. Describe the difference between chlorophyll

and chloroplasts.3. Where would a plant store energy?4. What is one of the main activities that take

place in mitochondria? Does this happen in a plant or an animal cell?

5. How do photosynthesis and cellular respiration “complement” each other?

6. What are the two main types of fermentation and what are their products?

7. Why do your muscles burn when you exercise?

All Cells Need EnergyPlant cells—energy from sunlightAnimal cells—energy from foodChemical energy—stored in

bonds between atoms of every molecule

Major source of energy is stored in a sugar molecule called glucose

PhotosynthesisPlants change the energy absorbed

from the sun into the chemical energy in glucose

Chlorophyll (pigment found in chloroplasts) traps the energy in sunlight

Carbon dioxide from air, water from soilenergy from sunlight changes CO2 and H2O into…glucose and oxygen (oxygen expelled as waste, glucose used for energy)

Glucose is used as well as storedStored glucose links together to

form a starch, which can later be broken back down to form glucose for energy

All Cells Release EnergyWhen the bonds of a sugar

molecule are broken down, energy is released that can be used by the cell

Two basic processes: cellular respiration and fermentation

Cellular RespirationTakes place in mitochondriaSugars and oxygenglucose in

cytoplasm is broken down releasing energy; after moving into the mitochondria, oxygen also enters in, combining with hydrogen to make waterenergy, carbon dioxide and water

Fermentation(Eukaryotic) Cells release energy

without oxygenTwo main types: alcoholic and lactic

acidProducts of alcoholic

fermentation:◦Bread

Products of lactic acid fermentation:◦Yogurt◦Cheese◦Sourdough bread

ExerciseDuring prolonged exercise, your body

uses all of its energy and oxygen, then relies on fermentation to break down sugars

When your cells use fermentation, it can cause a burning sensation in your muscles

After resting and breathing hard (taking in more oxygen), your muscles are able to finish releasing energy and store more energy to use for next time