Immune System worksheet for students to answer true/false statements and match words to clues about diseases and the immune system.

Immune System Worksheet Solution and Explanation

#### Part 1: True or False
1. Diseases are caused by bacteria.
- False: While many diseases are caused by bacteria, not all diseases are. Diseases can also be caused by viruses, fungi, parasites, or other factors like genetic disorders or environmental conditions.

2. If you are immune to something, it means that it will make you sick.
- False: Being immune to something means your body has developed the ability to fight off a specific pathogen (like a virus or bacteria) without getting sick. Immunity protects you from getting sick, not the opposite.

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#### Part 2: Matching Clues with Words
3. An illegal drug that destroys the immune system
- e. Marijuana: While marijuana is often associated with recreational use, excessive or prolonged use can negatively impact the immune system by altering its function.

4. A disease that destroys the immune system
- a. HIV: HIV (Human Immunodeficiency Virus) attacks and weakens the immune system by destroying CD4 cells, which are crucial for fighting infections.

5. Formed from dead white blood cells
- c. Pus: Pus is a thick fluid composed of dead white blood cells, bacteria, and cellular debris, often found at the site of an infection.

6. Made by white blood cells to fight diseases
- d. Antibodies: Antibodies are proteins produced by white blood cells (specifically B cells) to identify and neutralize foreign invaders like viruses and bacteria.

7. Negatively affects the cells in our brains
- g. Alcohol: Excessive alcohol consumption can damage brain cells and impair cognitive function over time.

8. The main defenders of the body
- j. White blood cells: White blood cells are the primary components of the immune system, responsible for identifying and eliminating pathogens.

9. Smoking damages this organ
- b. Lungs: Smoking primarily damages the lungs by causing inflammation, reducing lung capacity, and increasing the risk of lung cancer and other respiratory diseases.

10. Nicotine causes this organ to beat faster
- h. Heart: Nicotine is a stimulant that increases heart rate by constricting blood vessels and making the heart work harder.

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#### Part 3: Compare the Way a Virus Affects the Body with the Way a Bacteria Affects the Body
- Viruses:
- Viruses are much smaller than bacteria and cannot survive or reproduce outside a host cell.
- They invade living cells and hijack the cell's machinery to replicate themselves, often damaging or destroying the host cell in the process.
- Examples of viral diseases include the common cold, flu, HIV/AIDS, and COVID-19.
- Treatment for viral infections typically involves antiviral medications or boosting the immune system, as antibiotics are ineffective against viruses.

- Bacteria:
- Bacteria are single-celled organisms that can live independently and reproduce on their own.
- They can cause disease by producing toxins, invading tissues, or competing with beneficial bacteria in the body.
- Examples of bacterial diseases include strep throat, pneumonia, and tuberculosis.
- Bacterial infections are often treated with antibiotics, which target bacterial cells but do not affect human cells.

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Final Answer:

1. False
2. False

3. e. Marijuana
4. a. HIV
5. c. Pus
6. d. Antibodies
7. g. Alcohol
8. j. White blood cells
9. b. Lungs
10. h. Heart

11. Comparison:
- Viruses: Smaller, require a host cell to replicate, often destroy host cells, and are treated with antivirals or immune support.
- Bacteria: Larger, can live independently, cause disease through toxins or invasion, and are treated with antibiotics.

Final Boxed Answer:
\boxed{
\begin{array}{ll}
1. & \text{False} \\
2. & \text{False} \\
3. & \text{e. Marijuana} \\
4. & \text{a. HIV} \\
5. & \text{c. Pus} \\
6. & \text{d. Antibodies} \\
7. & \text{g. Alcohol} \\
8. & \text{j. White blood cells} \\
9. & \text{b. Lungs} \\
10. & \text{h. Heart} \\
11. & \text{See explanation above.}
\end{array}
}