Q12. Functions of the Components of Blood
Blood is a vital fluid in the body, consisting of various components, each serving essential functions:
- Red Blood Cells (RBCs):
- Transport oxygen from the lungs to body tissues.
- Carry carbon dioxide from tissues back to the lungs for exhalation.
- White Blood Cells (WBCs):
- Play a crucial role in the immune system.
- Defend the body against infections and foreign invaders.
- Platelets:
- Help in blood clotting to prevent excessive bleeding.
- Aid in wound healing by forming a protective barrier.
- Plasma:
- The liquid part of blood that carries nutrients, hormones, and waste products.
- Maintains blood pressure and regulates body temperature.
Q13. Blood Flow in Veins and Arteries
Veins and arteries have different structures, which influence blood flow:
- Veins:
- Contain valves that prevent backflow, ensuring blood returns to the heart.
- Blood flows due to muscle contractions and pressure changes during breathing.
- Arteries:
- Do not have valves but have thick, elastic walls.
- Blood flows in one direction due to high pressure generated by the heart's pumping action.
- Directional Flow:
- The heart's rhythm creates a pressure difference that propels blood through arteries and veins.
- The combination of heart contractions and vein valves ensures unidirectional flow throughout the circulatory system.
Q14. Heartbeat vs. Pulse Rate
Understanding the heartbeat and pulse rate is essential for grasping cardiovascular health:
- Heartbeat:
- Refers to the number of times the heart beats in a minute.
- Represents the heart's function as it pumps blood to the body.
- Pulse Rate:
- Is the number of times blood vessels expand and contract in response to each heartbeat.
- Can be felt at various points on the body, such as the wrist or neck.
- Comparison:
- Heartbeat is a direct measure of heart activity, while pulse rate indicates blood flow.
- Both are typically measured in beats per minute (BPM) but can differ slightly due to factors like heart health and vascular resistance.
- Conclusion:
- Both measures provide insight into cardiovascular health, with the heartbeat reflecting heart performance and pulse rate indicating overall circulation efficiency.