E. Answer the following questions.
1. Briefly explain the transport of water and minerals in plants.
Describe, in brief, the function of heart.
2.
3.
State the functions of the three types of blood vessels.
4.
Give one function each of RBC, WBC and platelets.
5.
Draw a neat and well labelled diagram of the human excretory system.
Dav
Answers
Answer:
Explanation:
1.Plants have two systems for the transportation of substances - using two different types of transport tissue. Xylem transports water and solutes from the roots to the leaves, while phloem transports food from the leaves to the rest of the plant. Transpiration is the process by which water evaporates from the leaves, which results in more water being drawn up from the roots. Plants have adaptations to reduce excessive water loss. Phloem transports synthesized food from the leaves to the rest of the plant body.
Water from the roots is pulled up by this tension. At night, when stomata close and transpiration stops, the water is held in the stem and leaf by the cohesion of water molecules to each other as well as the adhesion of water to the cell walls of the xylem vessels and tracheids.
2. Functions of the heart:
(i) It helps in the circulation of oxygen rich blood throughout the body by the pumping.
(ii) It receives oxygenated blood from the lungs.
(iii) It also pumps back the blood carrying carbon dioxide to the lungs.
(iv) It shows rhythmic contraction and relaxation for movement of blood.
3. Arteries. They carry oxygen-rich blood away from the heart to all of the body's tissues. ...
Capillaries. These small blood vessels connect the arteries and the veins. ...
Veins. These are blood vessels that take blood back to the heart.
4.RBC : Red blood cells carry oxygen around the body.
WBC :white blood cells eat or kill bacteria which enter the blood and save us from many diseases.
PLATELETS : platelets helps in clotting of blood in a cut or wound.