1. Which of the following joints allows for side-to-side bending movements?

A. Hinge joint
B. Ball-and-socket joint
C. Gliding joint
D. Saddle joint

Correct answer: C

Rationale: The correct answer is C: Gliding joint. Gliding joints are found where the bones meet and allow for limited side-to-side and back-and-forth movements. These joints have flat or slightly curved surfaces that glide against each other, enabling smooth motion in multiple directions. Hinge joints (A) allow for movement in one plane like a door hinge, ball-and-socket joints (B) allow for a wide range of motion in multiple directions, and saddle joints (D) allow for back-and-forth and side-to-side movements but are primarily designed for flexion and extension like the joint at the base of the thumb.

2. What is the term for the number of moles of solute per liter of solution?

A. Molarity
B. Molality
C. Normality
D. Concentration

Correct answer: A

Rationale: Molarity is defined as the number of moles of solute per liter of solution. The other choices are different concentration units.

3. What is the name for the mixture of reactants and products present during a chemical reaction?

A. Solution
B. Mixture
C. Reaction mixture
D. Precipitate

Correct answer: C

Rationale: This mixture contains both the starting materials (reactants) and the newly formed substances (products) during the reaction process.

4. Define "friction" in terms of opposing motion.

A. A force that increases motion
B. A force that accelerates motion
C. A force that opposes motion
D. A force that creates motion

Correct answer: c

Rationale: Friction acts opposite to the direction of motion, resisting or slowing down the movement of objects.

5. Antigenic variation, a common strategy used by some viruses, allows them to:

A. Produce toxins
B. Evade the immune system
C. Survive outside a host
D. Replicate rapidly

Correct answer: B

Rationale: Rationale: Antigenic variation is a strategy used by some viruses to evade the host's immune response. By constantly changing their surface antigens, viruses can avoid recognition and destruction by the immune system. This allows the virus to persist in the host and continue replicating, leading to prolonged infection and potential transmission to other hosts. Antigenic variation does not directly involve the production of toxins, survival outside a host, or rapid replication, making options A, C, and D incorrect in this context.

6. Which of the following is NOT a type of intermolecular force?

A. Hydrogen bonding
B. Dipole-dipole interactions
C. Ionic bonding
D. London dispersion forces

Correct answer: C

Rationale: Ionic bonding is a type of intramolecular force, holding ions together within an ionic compound. Intermolecular forces are responsible for the interactions between individual molecules.