Plant Physiology and Blood Transfusion Quiz

Which two main respiratory gases are involved in gaseous exchange in plants?

• Nitrogen and Oxygen

• Carbon (IV) Oxide and Oxygen

• Water vapor and Carbon (IV) Oxide

• Hydrogen and Oxygen

What is the primary function of stomata in leaves?

• To transport water and minerals throughout the plant.

• To store excess food for the plant.

• To provide surfaces for gaseous exchange.

• To give structural support to the leaf.

Which of the following is a structural adaptation of guard cells for their function?

• Uniformly thickened cell walls

• Lack of chloroplasts

• Uneven thickness of their cell walls

• Rectangular shape

According to the Photosynthetic Theory, what causes the stomata to open during the day?

• The guard cells become flaccid.

• Sugars are converted to starch, lowering osmotic pressure.

• Sugars produced increase osmotic pressure, causing guard cells to draw water and become turgid.

• Carbon (IV) oxide accumulates in the guard cells.

What happens to the stomata during the night according to the Starch-sugar interconversion theory?

• They open due to increased pH.

• They remain open as glucose is produced.

• They close as glucose is converted to starch, leading to water loss and flaccid guard cells.

• They swell and bulge outwards.

What is the role of lenticels in woody stems and roots?

• Photosynthesis

• Water absorption

• Gaseous exchange

• Storage of food

Which layer of young roots gives rise to root hairs?

• Cortex

• Endodermis

• Piliferous layer

• Root cap

What is the primary function of root hairs?

• Anchorage

• Storage of food

• Absorption of water and mineral salts

• Gaseous exchange

How do root hair cells absorb water from the soil by osmosis?

• Their cell sap has a lower solute concentration than the soil water.

• They actively pump water into the cell.

• Their cell sap has a higher solute concentration, making it hypertonic to soil water.

• The cell wall is impermeable to water.

What is active transport in the context of mineral salt absorption by roots?

• Movement of minerals with the concentration gradient.

• Movement of minerals without the use of energy.

• Movement of minerals against the concentration gradient, requiring energy.

• Movement of water molecules into the root hairs.