Energy to Survive Flashcards
Where does our energy come from?
Earth’s main source of energy is from the sun (solar energy)
How do animals get their energy?
Animals cannot directly use solar energy, so we rely on plants’ ability to convert light energy into chemical energy. (this process is called photosynthesis)
How do plants get their energy?
Through converting light energy to chemical energy
What is this process (of plants getting their energy) called?
Photosynthesis
What are the two main stages of photosynthesis?
Light dependant stage:
Light energy splits water to form oxygen and hydrogen
Light independent stage:
The hydrogen combines with carbon dioxide to form glucose, a simple sugar made up of carbon, hydrogen, and oxygen
Write the word equation for photosynthesis.
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Light
Carbon Dioxide + Water ————-> Glucose + Oxygen
Chlorophyll
What parts of a plant cell are involved in photosynthesis?
Mesophyll (contain chloroplasts (which contain chlorophyll))
Stomata
Xylem
Phloem
Guard cells
Know the function of the mesophyll, xylem, phloem, guard cells and stomata.
Mesophyll - contains chloroplasts which is where photosynthesis occurs
Xylem - Transports water from the roots to the leaves
Phloem - Transports food from the leaves to the rest of the plant
Guard cells - Opens and closes stomata
Stoma - Control the intake of CO2 and expelling of O2
Write the correctly balanced formula equation for photosynthesis.
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Light
6CO2 + 6H2O ————-> C6H12O6 + 6O2
Chlorophyll
What happens to the energy produced by photosynthesis in plants?
It’s made into glucose, a simple sugar made up of carbon, hydrogen, and oxygen.
Glucose is used for growth and repair around the plant.
Ec\xcess glucose is converted to other chemicals for storage in leaves, roots, and stems eg. starch, and cellulose.
Is energy absorbed or released in the photosynthesis reaction?
Absorbed
What is the difference between autotrophs and heterotrophs?
Autotrophs - Synthesise their own organic molecules
Heterotrophs - Ingest organic molecules
What is cellular respiration?
The conversion of stored energy (glucose) in all living organisms into usable energy
Why is it called cellular respiration?
because the cell seems to “respire” in a way that it takes in molecular oxygen and releases carbon dioxide.
What is the energy produced used for?
growth, repair, and movement
How are the equations for photosynthesis and respiration related?
Basically the same just flipped
What is the word and balanced equation for respiration?
Glucose + Oxygen —> Carbon Dioxide + Water + Energy
C6H12O6 + 6O2 —> 6CO2 + 6H2O + ATP
How is the equation for respiration similar and different from the equation for photosynthesis?
Be able to compare aerobic and anaerobic respiration.
Know the word equations for anaerobic respiration (fermentation) in animals and bacteria/fungi/yeast.
glucose —> lactic acid + energy (ATP)
glucose —> ethanold + carbon dioxide + energy (ATP)
Know applications of anaerobic respiration in yeast
What does ATP stand for?
Adenosine Triphsophate
What is ATP and what does it do?
Major source of energy for all cells
ATP molecules transfer energy around the cell
The difference between breathing and cellular respiration?
What are the differences between the roles of chloroplasts and mitochondria?
Chl
What is the energy transformation that occurs in photosynthesis?
light energy to chemical energy
What is the energy transformation that occurs in respiration?
chemical energy to atp and heat
What happens to the temperature of the solution in an endothermic reaction?
it warms up
What is the difference between a process and a reaction?
process changes to the physical structure reaction chemical structure
Give two examples of endothermic reactions.
photosynthesis, thermal decomposition
Give two examples of exothermic processes.
freezing ice, burning wood
How would you test to see if a reaction is endothermic?
change in temperture of thung
What is an enzyme?
biological catalysts (typically proteins) that significantly speed up the rate of chemical reactions
What is activation energy in a reaction?
activition enerfy is like a ‘hurdle’ rhar reactants need to get over t start chemical reaction if the hurdle to big it wont happen enzyme lower it
Explain how enzymes speed up the rate of a reaction (linking to activation energy).
reducing activation energy
Be able to use a labelled diagram to show how enzymes work. Be able to identify the active site, substrate and products.
What is a common ending for the name of enzymes? Give three examples.
ase
What is denaturation? What causes denaturation of enzymes?
Briefly summarise the effect of temperature (both high and low) on enzyme activity
Briefly summarise the effect of pH (both high and low) on enzyme activity
What is the definition of energy?
List four different types of kinetic energy
What are the units for energy?
Joule (J)
State the Law of conservation of energy.
What is metabolism?
Name the three main nutrients in food.
What is specific heat capacity?
Know how to use the specific heat capacity to calculate the energy transferred into water.
Know how to calculate the energy in food (using e = mcΔt)
E = Energy measured in Joule (J)
M = mass of water in gram
C = specific heat capacity of water (4.2)
^(delta) = change in temperature
Energy released from food per gram = mass of water(g)
