1. Hair follicles are openings in the skin that house

A. Blood vessels (Blood vessels are not housed in hair follicles)
B. Nerve endings (Nerve endings are present but not housed within)
C. Hair shafts and hair roots
D. Sebaceous glands (These glands are often attached to hair follicles)

Correct answer: C

Rationale: Hair follicles are structures in the skin that house both the hair shaft and the hair root. The hair shaft is the visible part of the hair that extends from the skin's surface, while the hair root is the part embedded within the hair follicle and extends into the deeper layers of the skin. The sebaceous glands, which produce sebum (an oily substance), are typically attached to hair follicles and help lubricate and protect the hair and skin. Blood vessels and nerve endings are present in the skin but are not housed within the hair follicles themselves. Therefore, the correct answer is C, as hair follicles contain both the hair shaft and hair root.

2. In a chemical reaction, the total amount of:

A. Matter remains the same
B. Matter increases
C. Matter decreases
D. Energy remains the same

Correct answer: A

Rationale: The Law of Conservation of Mass states that matter cannot be created or destroyed in a chemical reaction, only rearranged

3. Which organelle is responsible for carrying out photosynthesis in plant cells?

A. Golgi apparatus
B. Mitochondria
C. Chloroplasts
D. Lysosomes

Correct answer: C

Rationale: Rationale: A) Golgi apparatus: The Golgi apparatus is responsible for modifying, sorting, and packaging proteins for secretion or for use within the cell. It is not involved in photosynthesis. B) Mitochondria: Mitochondria are known as the powerhouse of the cell and are responsible for generating energy in the form of ATP through cellular respiration. They are not involved in photosynthesis. C) Chloroplasts: Chloroplasts are the organelles responsible for carrying out photosynthesis in plant cells. They contain chlorophyll, a pigment that captures light energy and converts it into chemical energy in the form of glucose. D) Lysosomes: Lysosomes are membrane-bound organelles that contain digestive enzymes to break down waste materials and cellular debris. They are not involved in photosynthesis. Therefore, the correct answer is C) Chloroplasts, as they are specifically responsible for carrying out photosynthesis in plant

4. Which of the following structures is responsible for preventing the backflow of blood from the left ventricle into the left atrium?

A. Aortic valve
B. Pulmonary valve
C. Tricuspid valve
D. Mitral valve

Correct answer: D

Rationale: The correct answer is D, the mitral valve. The mitral valve, also known as the bicuspid valve, is located between the left atrium and the left ventricle. Its main function is to prevent the backflow of blood from the left ventricle into the left atrium during ventricular contraction. The aortic valve (A) is responsible for preventing the backflow of blood from the aorta into the left ventricle, the pulmonary valve (B) prevents backflow from the pulmonary artery into the right ventricle, and the tricuspid valve (C) prevents backflow from the right ventricle into the right atrium. Therefore, the mitral valve is specifically responsible for preventing backflow in the left side of the heart, making it the correct answer in this case.

5. Which of the following is NOT a property of a catalyst?

A. Increases the rate of a reaction
B. Remains unchanged after the reaction
C. Lowers the activation energy
D. Creates new products

Correct answer: D

Rationale: A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It remains unchanged after the reaction, which eliminates option B. A catalyst works by lowering the activation energy required for the reaction to occur, which eliminates option C. A catalyst does not create new products in a reaction; it only facilitates the conversion of reactants into products more efficiently. Therefore, option D is NOT a property of a catalyst.

6. Describe the concept of inertia in terms of Newton's first law.

A. Objects in motion tend to remain in motion unless acted upon by an external force
B. Objects at rest tend to remain at rest unless acted upon by an external force
C. An object's resistance to a change in its state of motion
D. The force required to lift an object

Correct answer: c

Rationale: Inertia refers to an object's tendency to maintain its current state of motion (either at rest or in motion) unless acted upon by an external force.