Which evidence supports the theory of water movement by root pressure in flowering plants? 1 When the rate of transpiration of a tree is maximum, the diameter of the trunk is minimum. 2 When a plant shoot is removed close to the base of the stem, sap leaks out from the cut. 3 Evaporation of water from a porous pot can exert a force that draws water up a glass tube attached underneath the pot. 4 Droplets of water form at the edge of leaves of plants growing in conditions of soil with high water content and air with high humidity.

Which statement about the role of co-transporter proteins in the movement of sucrose is correct?

Why does an air bubble in a xylem vessel element stop the flow of water? 1 loss of adhesion 2 loss of cohesion 3 coll…

Which feature of some xerophytic leaves reduces the rate of transpiration by decreasing the water potential gradient …

What can combine with the haem group of a haemoglobin molecule? 1 oxygen 2 carbon dioxide 3 carbon monoxide

Which factors would help a person to adjust from living at a low altitude to living at a high altitude? 1 formation o…

Chronic obstructive pulmonary disease (COPD) includes bronchitis and emphysema. Which symptom is specific to emphysema?