respiration and photosynthesis Flashcards
why do cells need energy
Cells need energy to carry out their metabolic reactions. They start with the chemical energy stores in the molecules in food (sugars, carbohydrates and lipids) and convert it to a useful form such as adenosine triphosphate (ATP).
what are autographs
Autotrophs are organisms that use the process of photosynthesis to harvest light energy and use it to make sugars.
what is photosynthesis
Cells in autotrophs have a pigment molecule called chlorophyll that traps energy from sunlight and starts a chain of reactions called photosynthesis.
where is chloroplast located and what does it do
Chlorophyll is located in chloroplasts and gives plants and algae their green colour. Chlorophyll absorbs the energy in red and blue light and used it to build sugar molecules. Photosynthesis uses carbon dioxide and water to create glucose and oxygen. The process can be expressed as:
light energy
carbon dioxide + water ——> glucose + oxygen
chlorophyll
what is heterotrophs
Heterotrophs are organisms that eat sugars and carbohydrates made by autotrophs. Plant eating animals are examples of heterotrophs.
what is cell respiration
Cellular respiration is the process where heterotrophs break down the organic molecules using enzymes, this process releases chemical energy that can be used to run other processes in the cell. Carbon dioxide and water are products of cellular respiration.
what does cellular respiration do
Both heterotrophs and autotrophs use cellular respiration to release the chemical energy stored in sugars and fats located inside their cells.
what is the purpose of cell respiration
The purpose of cellular respiration is to produce ATP (energy). Cellular respiration can occur in the cytoplasm without oxygen (anaerobic) or in the mitochondria with oxygen (aerobic). Aerobic cellular respiration produces more ATP.
glucose + oxygen —————–> carbon dioxide + water
–> ATP
