Hematological & Lymphatic System – Lecture 1: Blood, Plasma, and Red Blood Cells

These flashcards review key points from the lecture on blood, plasma, and red blood cells, covering functions, composition, plasma proteins, formed elements, RBC structure, hemoglobin, and cell lifespan.

What three main components make up the cardiovascular system?

Pump (heart), tubes (blood vessels), and fluid (blood).

How is blood classified as a tissue?

A specialized fluid connective tissue containing cells suspended in a fluid matrix.

List the five primary functions of blood.

Transportation, regulation of pH/ions, stabilization of body temperature, defense against toxins/pathogens, and restriction of fluid loss at injury sites.

What percentage of body weight is blood volume?

Approximately 7 % of body weight.

State the average blood volumes for males and females.

Males: 5–6 L; Females: 4–5 L.

What are the normal temperature, viscosity, and pH of blood?

38 °C, about five times thicker than water, pH 7.35–7.45.

Name the two major components of whole blood.

Plasma and formed elements.

What proportion of whole blood is plasma?

About 55 % of blood volume.

Give the approximate composition of plasma by percentage.

Water 92 %, plasma proteins 7 %, other solutes 1 %.

Where are most plasma proteins produced?

The liver (more than 90 %).

Identify the three main categories of plasma proteins.

Albumin, globulins, and fibrinogen.

What percentage of plasma proteins is albumin, and what is its major function?

60 %; it maintains osmotic pressure and transports lipids such as triglycerides and cholesterol.

Distinguish between the two types of globulins and their roles.

Immunoglobulins (antibodies) for defense; transport globulins bind and carry substances such as thyroid hormones.

What is the role of fibrinogen?

It is required for blood clotting and forms insoluble fibrin.

Define serum.

The fluid that remains after clotting proteins (like fibrinogen) have been removed from plasma.

Which formed element makes up 99.9 % of cellular components in blood?

Red blood cells (erythrocytes).

State normal RBC counts for males and females.

Males: ~5.4 million/mm³; Females: ~4.8 million/mm³.

What is hematocrit (packed cell volume) and its typical values for males and females?

The percentage of blood volume occupied by cells; ~46 % in males, ~42 % in females.

Describe the shape of an RBC and its size.

A biconcave disc 7.2–8.4 µm in diameter, thinner in the center than the edge.

Why can mature RBCs not divide or synthesize proteins?

They lose their nucleus, ribosomes, and most organelles during development.

How long do RBCs live, and what percentage is replaced daily?

About 120 days; roughly 1 % are replaced each day.

List three structural/functional characteristics that aid RBCs in circulating effectively.

Large surface area for gas exchange, ability to form stacks (rouleaux) for smooth flow, and flexibility to pass through small capillaries.

Describe the subunit composition of hemoglobin.

Four globular chains (2 α and 2 β), each containing one heme with an iron atom.

How many oxygen molecules can one hemoglobin bind, and what is the oxygen-bound form called?

Up to four O₂ molecules; the complex is called oxyhemoglobin (HbO₂).

Where and how are aged or damaged RBCs removed from circulation?

Destroyed by phagocytes in the liver, spleen, and bone marrow or rupture (hemolyse) directly in circulation.

How do RBCs obtain energy without mitochondria?

Through anaerobic metabolism of glucose.