Blood is a specialized bodily fluid that circulates through the body, delivering essential nutrients and oxygen to cells and removing waste products. It is composed of red blood cells, white blood cells, platelets, and plasma.
Red blood cells (erythrocytes) are responsible for carrying oxygen from the lungs to the rest of the body and transporting carbon dioxide back to the lungs to be exhaled.
White blood cells (leukocytes) are part of the immune system and help to defend the body against infections and foreign invaders.
Platelets are small cell fragments that help with blood clotting and wound healing.
Plasma is the liquid component of blood that carries nutrients, hormones, and waste products throughout the body.
Overall, blood plays a crucial role in maintaining homeostasis and keeping the body functioning properly.
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Google Gemini AI
Aug 23
Definition of Blood
Blood is a specialized fluid that circulates throughout the body, delivering oxygen, nutrients, hormones, and other essential substances to cells while removing waste products.
Composition of Blood
Blood is made up of approximately 55% plasma and 45% blood cells:
1. Plasma
- Liquid component that makes up about 55% of blood volume - Consists of water, proteins (e.g., albumin, globulins), electrolytes, hormones, and other substances
2. Blood Cells
- Red blood cells (erythrocytes): Carry oxygen to tissues - White blood cells (leukocytes): Defend against infection and disease - Platelets (thrombocytes): Assist in blood clotting
Roles of Blood
1. Oxygen and Nutrient Transport:
- Transports oxygen from the lungs to tissues and carbon dioxide from tissues to the lungs for elimination. - Delivers nutrients, such as glucose, amino acids, and vitamins, to cells.
2. Waste Removal:
- Removes waste products, such as urea, creatinine, and bilirubin, from cells and transports them to the kidneys for excretion.
3. Hormone Transport:
- Carries hormones from endocrine glands to target tissues, regulating various physiological processes.
4. Immune Function:
- White blood cells protect the body from infection and disease by identifying and destroying foreign invaders.
5. pH Regulation:
- Buffers the blood to maintain a relatively constant pH, ensuring optimal functioning of cells.
6. Thermoregulation:
- Helps distribute heat throughout the body, maintaining a stable internal temperature.
7. Blood Clotting:
- Platelets play a crucial role in stopping bleeding by forming blood clots at sites of injury.
8. Fluid Balance:
- Regulates fluid balance between blood and tissues, preventing dehydration or overhydration.