Biology Test 3
What is the word equation for photosynthesis?
Carbon dioxide + water → glucose + oxygen
What is the balanced symbol equation for photosynthesis?
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
In which organelle does photosynthesis occur?
Chloroplast
What green pigment is essential for photosynthesis?
Chlorophyll
What is the main purpose of photosynthesis?
To produce glucose for energy and growth
Where does a plant get the carbon dioxide it needs for photosynthesis?
From the air, through the stomata
What is an endothermic reaction?
When energy is taken in from the surroundings e.g melting ice
What is an exothermic reaction?
When energy is released into the surroundings e.g combustion
What are some factors affecting the rate of photosynthesis?
Chlorophyll concentration
Carbon Dioxide concentration
Temperature
Light Intensity
What are the two types of respiration?
Aerobic respiration
Anaerobic respiration
What is respiration?
A chemical process that releases energy from glucose
What is the word equation for aerobic respiration?
Glucose + oxygen → carbon dioxide + water (+ energy)
Where does aerobic respiration occur in the cell?
In the mitochondria
What is a by-product of anaerobic respiration that is toxic and can lead to muscular pain and fatigue?
Lactic acid
What is the word equation for anaerobic respiration in animals?
Glucose → Lactic acid (+ Energy)
What is anaerobic respiration?
Respiration without oxygen.
What is the word equation for anaerobic respiration in yeast?
Glucose → Ethanol + Carbon dioxide (+ Energy)
Which produces more energy: aerobic or anaerobic respiration?
Aerobic respiration.
What is glucose used for in plants?
Respiration, making cellulose, amino acids, starch, and fats.
What gas is taken in during photosynthesis?
Carbon dioxide.
What gas is released during photosynthesis?
Oxygen.
Why do plants need light for photosynthesis?
Light provides the energy required to convert carbon dioxide and water into glucose and oxygen through chemical reactions in the chloroplasts.
Why does the rate of photosynthesis increase with temperature—up to a point?
Because enzymes that catalyze photosynthesis work faster at warmer temperatures, but if it's too hot, the enzymes denature and the rate drops.
Why do leaves have many chloroplasts?
To maximize the absorption of light, which is essential for photosynthesis.
Why do muscles switch to anaerobic respiration during intense exercise?
Oxygen supply can't meet demand, so muscles use anaerobic respiration to continue producing energy.
Why does breathing rate remain high after exercise?
To repay the oxygen debt by supplying oxygen to break down the lactic acid that built up during anaerobic respiration.
Why is respiration considered an exothermic reaction?
Because it releases energy in the form of heat and ATP during the breakdown of glucose.
Why is carbon dioxide concentration a limiting factor in photosynthesis?
Because it's a raw material for making glucose; if there's not enough CO₂, the rate of photosynthesis slows down.