Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Photosynthesis is the process by which plants make food using light energy, which primarily occurs in the leaves containing chlorophyll.
The Waxy Cuticle is a waterproof layer on top of the leaf that prevents excessive loss of through evaporation.
The Palisade Mesophyll consists of tall, cylindrical cells packed with chloroplasts to maximize the absorption of light for photosynthesis.
The Spongy Mesophyll has large air spaces between cells to allow for the efficient diffusion of gases like and .
Stomata are small pores, mostly on the underside of the leaf, controlled by guard cells to regulate gas exchange and the loss of water vapor (transpiration).
Vascular Bundles contain the Xylem, which transports and minerals from roots to leaves, and the Phloem, which transports glucose/sucrose produced during photosynthesis.
Root Hair Cells have long, finger-like projections that significantly increase the surface area for the absorption of via osmosis and mineral ions via active transport.
The Root Cap protects the growing tip of the root as it pushes through the soil.
📐Formulae
💡Examples
Problem 1:
Explain why most of the stomata are found on the lower epidermis of a leaf rather than the upper epidermis.
Solution:
To reduce water loss through transpiration.
Explanation:
The upper surface of the leaf is directly exposed to sunlight, which increases temperature. By having stomata on the cooler, shaded underside, the plant minimizes the evaporation of while still allowing to enter for photosynthesis.
Problem 2:
How does the structure of a root hair cell help in the uptake of and minerals?
Solution:
The long extension increases the surface area to volume ratio.
Explanation:
A higher surface area allows more molecules to pass through the cell membrane at once via osmosis. It also provides more space for carrier proteins involved in the active transport of mineral ions like (nitrates) from the soil.
Problem 3:
Identify the chemical symbol for the gas required by the spongy mesophyll for photosynthesis and the gas produced as a byproduct.
Solution:
Required: ; Produced: .
Explanation:
Plants take in Carbon Dioxide () from the atmosphere and release Oxygen () as a waste product of the photosynthetic reaction.