Reproduction in Plants & Flowers
What is the function of the stigma in a flower?
To receive pollen grains during pollination.
Where in the plant cell does photosynthesis occur?
Chloroplasts.
What is the role of digestion?
To break down food into soluble molecules for absorption.
What is respiration?
The process of releasing energy from glucose in cells.
Why is water considered essential for life processes in living organisms?
It acts as a solvent, allows chemical reactions to occur, and transports substances in organisms.
State two differences between wind and insect pollination.
Wind pollination uses light, small pollen and no scent/nectar; insect pollination uses heavy, sticky pollen with scent and nectar.
Name two raw materials required for photosynthesis.
Carbon dioxide and water.
Name the enzyme that digests starch.
Amylase.
Where does aerobic respiration take place?
Mitochondria.
A student plants two identical seeds: one is watered and placed in sunlight, the other is not watered. Predict and explain the outcome.
The watered plant in sunlight will grow because it can carry out photosynthesis and cellular processes; the other will fail due to lack of water for metabolism and transport.
Describe what happens during fertilization in a flowering plant.
Male gamete fuses with female gamete in the ovule to form a zygote.
Write the word equation for photosynthesis.
Carbon dioxide + water → glucose + oxygen (with light and chlorophyll).
Where does most absorption of digested food occur?
Small intestine.
Write the word equation for aerobic respiration.
Glucose + oxygen → carbon dioxide + water + energy.
Explain how the structure of red blood cells is adapted for oxygen transport and why this is important for respiration.
They are biconcave for large surface area, lack a nucleus for more hemoglobin, and transport oxygen efficiently to support aerobic respiration.
Explain why cross-pollination is generally more beneficial than self-pollination.
It increases genetic variation, improving adaptability and survival of the species.
Explain how light intensity affects the rate of photosynthesis.
Increasing light increases rate up to a point until another factor becomes limiting.
Explain how villi increase absorption efficiency.
They have thin walls, and a rich blood supply for quick transport.
Explain the difference between aerobic and anaerobic respiration.
Aerobic uses oxygen and releases more energy; anaerobic does not use oxygen and releases less energy.
A person suffers from severe anemia (low red blood cell count). Explain how this condition affects cellular respiration in the body.
With fewer red blood cells, less oxygen is transported to body cells, reducing aerobic respiration and ATP production, leading to fatigue and reduced energy levels.
A plant produces flowers but very few seeds. Suggest two possible reasons linked to reproduction.
Poor pollination, lack of pollinators, failure of pollen tube growth, or unsuccessful fertilization.
Describe two structural adaptations of leaves that help photosynthesis and explain their function.
Large surface area (more light absorption), thin leaf (short diffusion distance), many chloroplasts (more light trapping), stomata (gas exchange).
Compare mechanical and chemical digestion with examples.
Mechanical digestion physically breaks food (chewing, stomach churning); chemical digestion uses enzymes (amylase, protease, lipase) to break chemical bonds.
Explain why anaerobic respiration causes muscle fatigue during exercise.
Lactic acid builds up in muscles due to lack of oxygen, causing pain and fatigue.
A woman has a blockage in both fallopian tubes but continues to have a normal menstrual cycle. Explain why she is still unable to become pregnant, linking your answer to the process of fertilization and implantation.
Even though ovulation and menstruation still occur, the egg cannot travel through the fallopian tubes where fertilization normally takes place. As a result, sperm cannot meet the egg, so no zygote is formed. Without fertilization, there is no embryo to implant in the uterus, so pregnancy cannot occur.