AP BIOLOGY

Detailed explanation-1: -Water in the soil is absorbed by the roots and travels through the stems to the leaves. Water carries nutrients back and forth between roots and leaves. During photosynthesis, plant leaves need water, nutrients and sunlight to make their own food. Water also helps a plant to stay cool.

Detailed explanation-2: -Capillary action helps bring water up into the roots. With the help of adhesion and cohesion, water can work it’s way all the way up to the branches and leaves.

Detailed explanation-3: -As transpiration occurs, it deepens the meniscus of water in the leaf, creating negative pressure (also called tension or suction). The tension created by transpiration “pulls” water in the plant xylem, drawing the water upward in much the same way that you draw water upward when you suck on a straw.

Detailed explanation-4: -The main function of a stem in plants is that it helps in the conduction of water and minerals from the roots to the leaves and other parts of plants. It also provides support to branches, leaves, flowers, fruits, and buds of plants.

Detailed explanation-5: -Water from the soil enters the root hairs by moving along a water potential gradient and into the xylem through either the apoplast or symplast pathway. It is carried upward through the xylem by transpiration, and then passed into the leaves along another water potential gradient.