Bioenergetics Flashcards
Amino acid
small ‘building block’ molecule of proteins
Balanced diet
food with healthy proportions of protein, fat, carbohydrate, nutrients and minerals
Endothermic reaction
reaction where energy transferred to the environment
Fermentation
process using yeast to convert sugars into ethanol
Lactic acid
waste product from anaerobic respiration in muscle cells
Malnourishment
condition due to incorrect balance of foods to stay healthy
Metabolic rate
speed at which chemical reactions in the body occur
Metabolism
chemical reactions that keep the body alive
Oxygen debt
oxygen needed to react with and remove lactic acid after anaerobic respiration
Oxyhaemoglobin
molecule of haemoglobin and oxygen in the blood
Photosynthesis
process plants use to capture light energy from Sun, water and carbon dioxide goes to oxygen and glucose
Protein
large biomolecule made of chains of amino acids, many types and uses in the body
Starch
insoluble carbohydrate stored in plants
Equation for photosynthesis
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Limiting factors of Photosynthesis
- CO₂ concentration
- light intensity
- chlorophyll concentration
- temperature
Difference between transpiration and transpiration stream
Transpiration- evapouration of water at stomata
Transpiration stream- movement of water from roots to leaves via xylem
Required practical
Measures photosynthesis rate
What test do you hold to show a plant is photosynthesizing?
to test the leaf for presence of starch using iodine solution
Steps for testing for starch in a leaf
- put the leaf in boiling water to break down cell walls
- add a leaf to ethanol for 10 minutes with the bunsen off which removes cholorophyll from leaf (ethanol turns green)
- wash leaf in water to soften leaf
- place leaf on white tile and cover in iodine solution. If starch is present colour will change in areas containing chlorophyll
Experiment to test rate of transpiration
IV=
DV=
CV=
measures distance mved by air bubble/unit time
IV=humidity or temp or wind speed
DV= distance moved by air bubble
CV= light intensity, no. of leaves, species of plant
Uses for glucose
- Used for respiration (both aerobic and anaerobic)
- Converted into insoluble starch for storage in the stems, leaves and roots
- Used to produce fat or oil for storage (especially in seeds)
- Used to produce cellulose, which strengthens the cell wall
- Combined with nitrate ions absorbed from the soil to produce amino acids for protein synthesis
