1. Cartilage, a type of connective tissue, provides flexible support in various structures. Which of these does NOT contain cartilage?

A. Ears
B. Joints
C. Muscles
D. Nose

Correct answer: C

Rationale: Muscles do not contain cartilage. Cartilage is a specialized type of connective tissue that provides flexible support in structures like the ears, joints, and nose. Ears have cartilage in their structure, which helps maintain their shape and flexibility. Joints, such as the knee and elbow, have cartilage to cushion and reduce friction between bones. The nose also contains cartilage, forming its shape and structure. Muscles, on the other hand, are made up of muscle tissue and do not contain cartilage. Therefore, muscles are the correct answer as they do not contain cartilage, unlike the other options.

2. What is the name of a condition where the immune system mistakenly attacks healthy body tissues?

A. Allergy
B. Autoimmune disease
C. Immunodeficiency
D. Sepsis

Correct answer: B

Rationale: The correct answer is B: Autoimmune disease. This condition occurs when the immune system mistakenly targets and attacks healthy tissues in the body, leading to inflammation and tissue damage. Autoimmune diseases can affect various organs and systems in the body, such as rheumatoid arthritis, lupus, and multiple sclerosis. Allergies (A) involve the immune system overreacting to harmless substances, but they do not involve attacking healthy tissues. Immunodeficiency (C) refers to a weakened immune system that is less able to fight off infections. Sepsis (D) is a life-threatening condition caused by the body's response to an infection, not an autoimmune reaction.

3. Fingernails and toenails are made primarily of:

A. Collagen (Collagen is found in the dermis)
B. Keratin
C. Melanin (Melanin provides pigment, not structure)
D. Sebum (Sebum is an oily substance)

Correct answer: B

Rationale: The correct answer is B: Keratin. Fingernails and toenails are primarily made of a tough protein called keratin. Keratin is a fibrous structural protein that also makes up hair and the outer layer of skin. Collagen, as mentioned in option A, is found in the dermis of the skin and is responsible for providing strength and elasticity to the skin. Melanin, as in option C, is a pigment that gives color to the skin, hair, and eyes, but it does not contribute to the structure of nails. Sebum, as in option D, is an oily substance produced by the sebaceous glands in the skin to moisturize and protect the skin, but it is not a component of nails.

4. What is the largest lymphatic vessel in the body?

A. Jugular vein
B. Thoracic duct
C. Subclavian vein
D. Aorta

Correct answer: B

Rationale: The correct answer is B: Thoracic duct. The thoracic duct is the largest lymphatic vessel in the body, responsible for draining lymph from the lower half of the body, the left side of the head and neck, and the left arm. The jugular vein (A) and subclavian vein (C) are both blood vessels, not lymphatic vessels. The aorta (D) is the largest artery in the body, responsible for carrying oxygenated blood away from the heart. Understanding the anatomy of the lymphatic system is crucial for understanding the circulation and immune functions of the body.

5. What is the main function of estuaries?

A. Filtering pollutants from water
B. Providing habitat for marine life
C. Storing carbon dioxide
D. Generating wind power

Correct answer: B

Rationale: Rationale: Estuaries are coastal areas where freshwater from rivers and streams mixes with saltwater from the ocean. They serve as important habitats for a variety of marine life, including fish, birds, and other wildlife. Estuaries provide shelter, breeding grounds, and food sources for many species, making them crucial for the overall health of marine ecosystems. While estuaries can help filter pollutants to some extent, their primary function is to support and sustain diverse populations of plants and animals. Storing carbon dioxide and generating wind power are not main functions of estuaries.

6. The science of classifying organisms into different groups based on their evolutionary relationships is called:

A. Taxonomy
B. Microbiology
C. Genetics
D. Epidemiology

Correct answer: A

Rationale: Rationale: Taxonomy is the science of classifying organisms into different groups based on their evolutionary relationships. It involves identifying, naming, and categorizing living organisms according to their similarities and differences. Microbiology (option B) is the study of microorganisms, Genetics (option C) is the study of genes and heredity, and Epidemiology (option D) is the study of the distribution and determinants of health-related states or events in populations.