Class Notes NCERT Solutions for CBSE Students
Question: Why does the rate of heartbeat increase after running?
Answer: The sale of the heartbeat increases after running due to increase in circulation of blood as more blood is required to be pumped.
Question: In what ways are xylem and phloem important for tranportation of meterials in plants?
Answer: Flowering plants have a well developed transport system called a vascular system is composed of pipe like versels called xylem and phloem. Xylem transports water and minerals upwards from the roots. Phloem cells also from long-tubes for transportation of food. Phloem transports glucose made in the leaves to the other parts of the plants.
Question: Differentate between xylem and phloem.
Answer: Differentate between xylem and phloem are:
Question: What does circulatory system consists of? Give the main function of each?
Answer: The circulatory system consists o the blood, the blood vessels and the heart.
The blood – is a specialized bodily fluid that flows in blood vessels. It transports –
- Digested food from the small inters tine to all parts of the body.
- Blood cells are divided into three parts – WBC’s, RBC’s, Platelets.
The Blood vessels – Blood circulates across the body through a network of tubes called blood vessels. There are three types of blood vessels. – Arteries, Veins and Cappileries.
The Heart – It is fist-sized muscular organ located between the lungs. Its function is to pump blood to all parts of a body.
If you observe a drop of blood under a microscope, which cell would you see? What are the functions of the cell?
Answer: We can see three types cells – RBC’s, WBC’s, Platelets
- RBC’s – are disc shaped cell which contain a red-coloured protein called hemoglobin. It is this pigment that absorb oxygen and transports it to the cells all over the body.
- WBC’s – are sighity larger RBC’s. They are fewer in number than RBC’s. Their main job is to fight against diseases by destroying harmful bacteria and other fore in materials.
- Platelets – are small than red blood cells. They help the blood to clott whenever there is around in the body.
