Ch.10: Blood Flashcards
Blood transports everything that must be carried from one place to another, such as:
- Nutrients
- Wastes
- Hormones
- Body heat
Blood is the only fluid _____, a type of _____, in the human body
- Tissue
* Connective tissue
What are the components of blood?
- Formed elements (living cells)
* Plasma (nonliving fluid matrix)
When blood is separated:
• Erythrocytes sink to the bottom (45 percent of blood, a percentage known as the hematocrit)
• Buffy coat contains leukocytes and platelets (less than 1 percent of blood)
*Buffy coat is a thin, whitish layer between the erythrocytes and plasma
• Plasma rises to the top (55 percent of blood)
What are the characteristics of blood?
• Sticky, opaque fluid • Heavier and thicker than water • Color range *Oxygen-rich blood is scarlet red *Oxygen-poor blood is dull red or purple • Metallic, salty taste • Blood p H is slightly alkaline, between 7.35 and 7.45 • Blood temperature is slightly higher than body temperature, at 38°Celsius or 100.4°F
What is the volume of blood in the body?
- About 5–6 liters, or about 6 quarts, of blood are found in a healthy adult
- Blood makes up 8 percent of body weight
Plasma is __ water.
90%
Plasma includes many dissolved substances, such as:
- Nutrients
- Salts (electrolytes)
- Respiratory gases
- Hormones
- Plasma proteins
- Waste products
What are plasma proteins?
• Most abundant solutes in plasma • Most are made by the liver • Include: *Albumin *Clotting proteins *Antibodies
What is albumin?
An important blood buffer and contributes to osmotic pressure
What are clotting proteins?
Help to stem blood loss when a blood vessel is injured
What are antibodies?
Help protect the body from pathogens
Blood _____ varies as cells exchange substances with the blood.
- Composition
- Liver makes more proteins when levels drop
- Respiratory and urinary systems restore blood p H to normal when blood becomes too acidic or alkaline
Plasma helps distribute body _____.
Heat
What are erythrocytes and what are their function?
• Red blood cells (RBCs) • Main function is to carry oxygen • RBCs differ from other blood cells: *Anucleate (no nucleus) *Contain few organelles; lack mitochondria *Essentially bags of hemoglobin (Hb) *Shaped like biconcave discs • Normal count is 5 million RBCs per cubic millimeter (mm3) of blood
What are leukocytes and what are their function?
- White blood cells (WBCs)
- Crucial in body’s defense against disease
- Complete cells, with nucleus and organelles
- Able to move into and out of blood vessels (diapedesis)
- Respond to chemicals released by damaged tissues (known as positive chemotaxis)
- Move by amoeboid motion
- 4,800 to 10,800 W B Cs per mm3 of blood
What are platelets?
- Fragments of megakaryocytes (multinucleate cells)
- Needed for the clotting process
- Normal platelet count is 300,000 platelets per mm3 of blood
Hemoglobin is an _____ protein.
- Iron-bearing
- Binds oxygen
- Each hemoglobin molecule can bind 4 oxygen molecules
- Each erythrocyte has 250 million hemoglobin molecules
- Normal blood contains 12–18 grams of hemoglobin per 100 milliliters (m l) of blood
Concept Link 1
Recall that hemoglobin is an example of a globular protein (look back at Figure 2.19b, p.50). Globular, or functional, proteins have tertiary structure, meaning that they are folded into a very specific shape. In this case, the folded structure of hemoglobin allows it to perform the specific function of binding and carrying oxygen. The structure of globular proteins is also very vulnerable to p H changes and can be denatured (unfolded) by a p H that is too low (acidic); denatured hemoglobin is unable to bind oxygen.
What is the result of homeostatic imbalance of RBCs?
- Anemia
* Sickle cell anemia (SCA)
What is anemia?
- A decrease in the oxygen-carrying ability of the blood due to:
- Lower-than-normal number of RBCs
- Abnormal or deficient hemoglobin content in the RBCs
Sickle cell anemia (SCA) results from _____.
Abnormally shaped hemoglobin
What is polycythemia?
Disorder resulting from excessive or abnormal increase of R B Cs due to:
• Bone marrow cancer (polycythemia vera)
• Life at higher altitudes (secondary polycythemia)
Increase in RBCs slows _____ and increases _____.
- Blood flow
* Blood viscosity
What is leukocytosis?
- WBC count above 11,000 cells per mm3 of blood
* Generally indicates an infection
What is leukopenia?
- Abnormally low WBC count
* Commonly caused by certain drugs, such as corticosteroids and anticancer agents
What is leukemia?
- Bone marrow becomes cancerous
* Numerous immature WBC are produced
What are the types of leukocytes?
- Granulocytes
* Agranulocytes
What are agranulocytes?
• Type of leukocyte
• Lack visible cytoplasmic granules
• Nuclei are spherical, oval, or kidney-shaped
Include lymphocytes and monocytes
What are granulocytes?
- Type of leukocyte
- Granules in their cytoplasm can be stained
- Possess lobed nuclei
- Include neutrophils, eosinophils, and basophils
List of the WBCs, from most to least abundant:
- Neutrophils (never)
- Lymphocytes (let)
- Monocytes (monkeys)
- Eosinophils (eat)
- Basophils (bananas)
What are neutrophils?
- A type of granulocyte
- Most numerous WBC
- Multilobed nucleus
- Cytoplasm stains pink and contains fine granules
- Function as phagocytes at active sites of infection
- Numbers increase during infection
- 3,000–7,000 neutrophils per mm3 of blood (40-70% of WBCs)
What are eosinophils?
- A type of granulocyte
- Nucleus stains blue-red
- Brick-red cytoplasmic granules
- Function is to kill parasitic worms and play a role in allergy attacks
- 100–400 eosinophils per mm3 of blood (1-4 percent of WBCs)
What are basophils?
- A type of granulocyte
- Rarest of the W B Cs
- Large histamine-containing granules that stain dark blue
- Contain heparin (anticoagulant)
- 20–50 basophils per mm3 of blood (0-1 percent of WBCs)