3. OXYGENATION (Formed Elements)

What are formed elements in blood?

They are cells and cell fragments suspended in plasma.

What are the 3 types of formed elements?

Erythrocytes (RBCs), leukocytes (WBCs), and thrombocytes (platelets).

What percentage of blood is formed elements?

45% of blood is formed elements.

What percentage of blood is plasma?

55% of blood is plasma.

What are platelets?

Platelets (thrombocytes) are the smallest blood components and help control bleeding.

How do platelets stop bleeding?

They cluster together to form clots at injury sites.

Why are platelets near blood vessel walls?

Because they're the lightest, they're pushed to the edges, helping them reach injuries faster.

What is the normal platelet count in adults?

150,000 to 450,000 platelets per microliter of blood.

What are the two conditions resulting from abnormal platelet counts are?

1. Thrombocytopenia

2. Thrombocytosis

What is thrombocytopenia?

A low platelet count that can cause bruising and excessive bleeding.

What is thrombocytosis?

A high platelet count that can lead to abnormal clotting, possibly causing heart attack or stroke.

What causes thrombocytosis?

Abnormal bone marrow cells make too many platelets, though the exact cause is unknown.

What are the 5 types of LEUKOCYTES (WBC)?

1. Neutrophils

2. Lymphocytes

3. Monocytes

4. Eosinophils

5. Basophils

What are neutrophils?

Neutrophils are the most common type of white blood cell and the first line of immune defense.

What do neutrophils do?

They fight infections by blocking, disabling, and digesting harmful microorganisms.

How do neutrophils help in inflammation?

They trigger tissue repair during redness and swelling to heal injury or damage.

What are lymphocytes?

Lymphocytes are a type of immune cell found in the blood and lymphatic system.

Where are mature lymphocytes found?

In the blood and throughout the lymphatic system.

What are the two main types of lymphocytes?

T lymphocytes (T cells) and B lymphocytes (B cells).

What do T cells do?

T cells control immune responses and directly kill infected or cancerous cells.

What do B cells do?

B cells produce antibodies that target viruses, bacteria, and other invaders.

Why don't you get some infections twice?

Because B cells "remember" pathogens and make antibodies for long-term protection.

How do lymphocytes help the immune system?

They fight off cancer, viruses, and bacteria (antigens).

What are monocytes?

Monocytes are immune cells that transform into macrophages or dendritic cells when they detect invading germs.

What do monocytes differentiate into?

Macrophages and Dendritic cells

What do macrophages do?

Macrophages kill germs by surrounding and digesting them with toxic enzymes, and they also clear dead cells.

What do dendritic cells do?

Dendritic cells alert other immune cells to fight infection and are found in tissues like skin, lungs, and the gut.

What are eosinophils?

Eosinophils are white blood cells that defend against parasites, allergens, and foreign organisms.

How common are eosinophils?

They make up less than 5% of all white blood cells.

How do eosinophils work?

They release toxic granules to kill and digest invading organisms.

What are basophils?

Basophils are white blood cells that help defend against allergens, pathogens, and parasites.

What do basophils release during allergic reactions?

They release histamine and heparin.

What is the function of histamine and heparin?

Histamine increases blood flow, and heparin prevents blood clotting.

What are erythrocytes (RBCs)?

Red blood cells deliver oxygen to tissues and carry carbon dioxide waste back to the lungs.

Where are RBCs made?

They are produced in the bone marrow and mature in about seven days.

What protein do RBCs contain?

They contain hemoglobin, which carries oxygen.

What are Medical conditions that affect a low red blood cell count?

1. Anemia

2. Blood loss

3. Bone marrow disorder

4. Cancer

What is anemia?

It's a condition where your blood carries less oxygen, making you feel cold, tired, and weak.

What is blood loss in this context?

It means your body is losing more red blood cells than it can replace.

What happens with bone marrow disorders?

They damage the marrow where red blood cells are made, like in leukemia or lymphoma.

How does cancer affect RBC count?

Certain cancers and chemotherapy can lower red blood cell production.

What are Medical conditions that affect a high red blood cell?

1. Polycythemia vera

2. Congenital heart disease

3. Lung disease

4. Hypoxia

5. Carbon monoxide

What is polycythemia vera?

It's a condition where too many red blood cells make the blood thick, increasing the risk of stroke or heart attack.

What is congenital heart disease?

A defect in the heart that forms before birth and affects oxygen flow.

How do lung diseases raise RBC count?

Diseases like COPD and fibrosis reduce oxygen, so the body makes more RBCs to compensate.

What is hypoxia?

A condition where blood oxygen levels are too low.