Hormone & Transportation System in Plants

What triggers the opening of stomata in plant leaves?

• 1. Increased levels of carbon dioxide

• 1. Decreased levels of oxygen

• 1. Presence of sun light

• 1. High humidity levels

What is the primary force responsible for the movement of water through the xylem in the

cohesion-tension model?

• 1. Root pressure

• 1. Capillarv action

• 1. Cohesion between water molecules

• 1. Active transport by cells

There are 2 pathways of water and mineral

uptake. There's pathway A, which is between

porous cell walls and there's pathway B which is….

• through cells across the cortex and enderdemis.

• 1. outside cell walls

• 1. through air inside the soil.

• 1. through water across the soil.

Which one used to transport water?

• xylem

• phloem

• pericycle

• cortex

Where is auxin produced?

• root tips

• style

• petriole

• shoot apical meristem

What is the lon required for the opening and

closing of stoma?

• 1. Ca2+

• Mg2+

• Na+

• K+

What radioactive substance is used to study the transportation of organic nutrients from source to sink?

• 1. Carbon-12

• 1. Sodium-24

• 1. Carbon-14

• 1. Phosphorus-32

What is the reason organic nutrients are not

transported passively?

• 1. Longer time taken

• 1. Due to gravity

• 1. The distance between source and sink is far

• 1. The pressure-flow model cannot transportsThe pressure-flow model cannot transports

  2. organic substance via simple osmosis like water

which hormone prevent aging of plant?

• cytokinin

• auxin

• ethylene

• antidiuresis

which hormone closes stomata?

• adrenaline

• abscicic acid

• cytokinin

• oxytocin