1. Skeletal muscles are attached to bones by tough connective tissues called

A. Ligaments
B. Tendons
C. Cartilage
D. Fascia

Correct answer: B

Rationale: The correct answer is B: Tendons. Skeletal muscles are connected to bones by tendons, which are tough connective tissues that transmit the force generated by the muscle to the bone, allowing movement. Ligaments (A) connect bone to bone and provide stability to joints. Cartilage (C) is a smooth, firm tissue that covers the surface of bones at joints, reducing friction and absorbing shock. Fascia (D) is a connective tissue that surrounds muscles and other structures, providing support and protection.

2. What property of matter remains constant regardless of changes in its state?

A. Mass
B. Volume
C. Density
D. Weight

Correct answer: a

Rationale: Mass remains constant for a given amount of matter, regardless of its state (solid, liquid, or gas) or its location in the universe. Explanation of other options:

3. Which property of a substance refers to the force exerted on an object due to gravity?

A. Mass
B. Weight
C. Density
D. Volume

Correct answer:

Rationale: Weight is the measure of the force exerted on an object due to gravity. It is calculated as mass multiplied by the acceleration due to gravity.

4. What is the periodic table?

A. A table of elements that are arranged in order of increasing atomic number.
B. A table of elements that are arranged in order of increasing atomic mass.
C. A table of elements that are arranged in order of their reactivity.
D. A table of elements that are arranged in order of their color.

Correct answer: B

Rationale: The periodic table is a tabular arrangement of the chemical elements, organized on the basis of their atomic number, electron configurations, and recurring chemical properties. Elements are arranged in rows (periods) and columns (groups) with similar properties. The elements are listed in order of increasing atomic number, which is the number of protons in the nucleus of an atom. This arrangement reveals a periodic repetition of chemical properties, which is the basis of the periodic law.

5. What is the myelin sheath and what does it do?

A. A group of nerve cells that perform a specific function.
B. A fatty substance that insulates some nerve fibers.
C. A fluid-filled cavity within the brain.
D. The junction between two neurons.

Correct answer: B

Rationale: The correct answer is B. The myelin sheath is a fatty substance that insulates some nerve fibers. It is essential for the proper functioning of the nervous system as it acts as an insulator, allowing for faster transmission of nerve impulses along the axon. Without the myelin sheath, nerve signals could be disrupted or weakened, leading to issues with movement, sensation, and other neurological functions. Options A, C, and D are incorrect as they do not accurately describe the myelin sheath or its function.

6. Which of the following is NOT a common symptom of lactose intolerance?

A. Gas
B. Bloating
C. Diarrhea
D. Nausea

Correct answer: D

Rationale: Rationale: A) Gas: Gas is a common symptom of lactose intolerance. When lactose is not properly digested, it can ferment in the colon, leading to the production of gas. B) Bloating: Bloating is another common symptom of lactose intolerance. The buildup of gas in the digestive system can cause bloating and discomfort. C) Diarrhea: Diarrhea is a common symptom of lactose intolerance. When lactose is not broken down in the small intestine, it can draw excess water into the colon, resulting in diarrhea. D) Nausea: Nausea is not a common symptom of lactose intolerance. While some individuals may experience mild stomach discomfort or cramps, nausea is not typically associated with lactose intolerance.