Plant Transport AQA A level biology

What is the correct definition of osmosis?

• The movement of water from a region of more negative water potential to a region of less negative water potential through a partially permeable membrane

• The movement of water from a low water concentration to a water high concentration through a partially permeable membrane.

• The movement of water from a region of high water potential (less negative) to a region of lower water potential (more negative) through a partially permeable membrane

• The movement of water from a region of low water potential (less negative) to a region of higher water potential (more negative) through a partially permeable membrane

The evaporation of water from the stomata of the leaves is known as?

• Root pressure

• Translocation

• Transpiration

• cohesion tension theory

• osmosis

What molecule lines the xylem vessels in a spiracle fashion so that it provide strength from collapsing under pressure.

• Cellulose

• Starch

• Chitin

• Lignin

• Glycogen

What statement(s) is/ are incorrect about xylem vessels

• Mature xylem consist of dead cells.

• Mature xylem are elongated end-to-end.

• Mature xylem contain lignin to provide strength

• Mature xylem contains cytoplasm, mitochondria, and a nucleus

• Mature xylem transport sugars and cell sap

Water enters the root by osmosis. What process aids the uptake of water in the root?

• Active transport of glucose into the root from the soil

• Active transport of glucose out of the root into the soil

• Active transport of ions into the root from the soil

• Active transport of ions out of the root and into the soil

What factors speed up the rate of transpiration

• Number of stomata

• High humidity outside of the leaf

• High wind speed

• High air temperature

• Water trapped on hairs of the leaf lowering the water potential difference between the cells and the air.

What cell actively transports sugars into the phloem sieve tube elements (9,5)

Translocation is

• The movement of water from a roots to stem by osmosis through xylem tissue

• The movement of organic molecules and some mineral ions from a source to a sink through xylem tissue

• The movement of organic molecules and some mineral ions from a source to sink through phloem tissue

• The movement of water from a roots to stem by osmosis through phloem tissue

What causes the movement of sugars through the sieve tube elements in the phloem tissue?

• Facilitated diffusion of water from the xylem to the phloem generating high pressure.

• The movement of water from the xylem into the phloem by osmosis generating high Hydrostatic pressure.

• The movement of water from the xylem into the phloem by osmosis generating low Hydrostatic pressure.

• The movement of water from the phloem into the xylem by osmosis generating high Hydrostatic pressure.

• The movement of water from the phloem into the xylem by osmosis generating low Hydrostatic pressure.

Sugar loaded into the sieve tube elements by what mechanism? (6,9)