Introduction

Question 1

List the 3 main functions of the lymphatic system. (3)

Answer 1

1. Absorbing fat and fat-soluble vitamins from the small intestines
2. Removing waste from the tissues
3. Providing aid to the immune system

Question 2

What colour is lymph usually and where + why is it different? (2)

Answer 2

1. Most lymph in the body is clear

2. In the lacteals, it is a creamy white due to the high concentration of lipids

Question 3

Which way does the lymph flow and what is this system called? (2)

Answer 3

1. Lymph flows towards the heart

2. One-way system (lymphatics in this case specifically)

Question 4

Define: lymph

Answer 4

Excess tissue fluid

Question 5

What is the purpose of lymph capillaries?

Answer 5

Aid in digestion by absorbing lipids

Question 6

What type of cells do lymph nodes contain?

Answer 6

Lymphocytes

Question 7

What is the main purpose of lymphocytes?

Answer 7

Destroy pathogens; remove foreign material

Question 8

Name and list the functions of the two major categories of lymphocytes. (2)

Answer 8

1. Macrophages → engulfs and destroys bacteria, viruses, and foreign substances
2. Lymphocytes → responds to foreign substances in the lymphatic system

Question 9

List the 4 other lymphatic organs and briefly describe each. (4)

Answer 9

1. Spleen → cleans and filters the blood and destroys worn-out RBCs
2. Thymus → produces thymosin = the hormone which functions in programming certain lymphocytes
3. Tonsils → traps and removes any bacteria or other foreign pathogens entering the throat
4. Peyer’s Patches → tonsil-like organ found in the wall of the distal part of the small intestines

Question 10

What are the two defense systems of the body and how do they respond to foreign substances? (2)

Answer 10

1. Innate defense system → responds immediately to protect the body
2. Adaptive defense system → mounts an attack against the particular foreign substances

Question 11

What are the body’s first lines of defense against invasions of pathogens? (2)

Answer 11

1. Skin

2. Mucous membrane

Question 12

Define: lysosomes

Answer 12

Enzymatic organelle which destroys bacteria

Question 13

Where are lysosomes found? (3)

Answer 13

1. Tears
2. Saliva
3. Other secretions

Question 14

What is an inflammatory response?

Answer 14

A non-specific response that is triggered whenever body tissues are injured

Question 15

List 4 common indicators of active inflammation. (4)

Answer 15

1. Redness
2. Heat
3. Swelling
4. Pain

Question 16

What do cells release when they are injured and what do those substances function as? (3)

Answer 16

1. Histamines
2. Kinins
3. A chemical alarm/alert to the rest of the body

Question 17

What is the purpose of the inflammatory response?

Answer 17

To prevent the spread of damaging agents to nearby tissue

Question 18

Define: pus

Answer 18

Mixture of dead or dying neutrophils, broken-down tissue, and living + dead pathogens

Question 19

State the purpose of antimicrobial proteins and name the two most important types. (3)

Answer 19

1. Enhance the innate defenses either by attacking microorganisms directly or by hindering their ability to respond
2. Complement proteins
3. Interferon

Question 20

Define: complement proteins

Answer 20

Group of >20 plasma proteins that circulate the blood in an inactive state

Question 21

Define: interferon

Answer 21

Viruses → essentially nucleic acids surrounded by a protein coat

Question 22

What do viruses lack?

Answer 22

The cellular machinery required to generate ATP (mitochondria)

Question 23

What is the main symptom of a fever and what is a fever in regards to foreign substances? (2)

Answer 23

1. High body temperature

2. Systemic response to invading microorganisms

Question 24

What part of the body regulates temperature?

Answer 24

Hypothalamus