Respiration Flashcards
define respiration
the release of energy from food
where is energy released from food
in all the cells mitochondrias of the body
define energy
the ability to do work
define work
work is done when a force moves an object
word equation for respiration
glucose + oxygen = energy + carbon dioxide + water
chemical equation for respiration
C6H12O6 + 6O2 = energy + 6CO2 + 6H2O
how is respiration and photosynthesis a chemical process
involves a number of steps where new substances are formed
how is respiration a biological process
takes place in living cells and uses enzymes
what are the 7 characteristics of life
Movement Respiration Sensitivity Growth Reproduction Excretion Nutrition
what three factors affect respiration
glucose , oxygen availability
temperature
why does temperature affect respiration
enzymes can’t work if it’s too cold
enzymes are killed if it’s too hot
investigate how temperature affects rate of respiration
four water baths with 10,20,30,40C. test tube with glucose solution and yeast in each, left for 6 minutes. Observe different heights of foam.
CONCLUSION: an increase in temp from 10 to 40 causes an increase in rate of respiration
3 ways earth depends on photosynthesis
provide food, oxygen and clean air
define photosynthesis
the way green plants make their own food by using light
word equation for photosynthesis
carbon dioxide + water, chlorophyll/sunlight glucose + oxygen
chemical equation for photosynthesis
6CO2 + 6H2O chlorophyll/sunlight C6H12O6 + 6O2
how does photosynthesis happen?
- the plant gets all the stuff needed for the equation
- co2 and water combine in chloroplasts to make glucose by using energy from sunlight .
- oxygen is given off as a waste product
how does the plant get carbon dioxide ?
from air through tiny pores on the leaf called stomata
how does the plant get water?
from the soil through roots
how does the plant get sunlight?
chlorophyll in chloroplasts of leaf cells absorb it
what energy conversion happens in photosynthesis?
light to chemical
what 3 factors affect photosynthesis?
co2 bc it reacts w water
temperature bc of enzymes
light bc it transforms to chemical energy
show that light is necessary for photosynthesis
place plant in darkness for 24 hours to destarch it. then cover a leaf with aluminium foil w paper clips. then leave in sunlight for 6 hours. Test two leaves for starch:
put in boiling water to soften
place a test tube with methylated spirits in the beaker with hot water. put leaf inside to remove chlorophyll - it will become white . water shouldn’t boil bc alcohol has a lower boiling rate
put leaves back in hot water to remove alcohol
place on white tile to observe colour change
drop iodine solution - blueblack has starch
how to use knowledge of factors of photosynthesis to increase crop yields ? 3
increase light w artificial lights
increase co2 by burning gas in greenhouses
increase temperature
