1. The tiny contractile units within muscle cells are called:

A. Myocytes
B. Myofibrils
C. Sarcomeres
D. Tendons

Correct answer: C

Rationale: The correct answer is C: Sarcomeres. Sarcomeres are the basic contractile units within muscle cells. They are made up of overlapping filaments of actin and myosin proteins, which slide past each other during muscle contraction, resulting in muscle movement. Myocytes (A) are muscle cells, myofibrils (B) are cylindrical structures within muscle fibers composed of sarcomeres, and tendons (D) are tough bands of connective tissue that connect muscle to bone. Therefore, sarcomeres are specifically responsible for muscle contraction within muscle cells.

2. The ability of a substance to dissolve in another is called:

A. Solubility
B. Miscibility
C. Immiscibility
D. Reactivity

Correct answer: A

Rationale: Solubility refers to the extent to which one substance can dissolve in another to form a homogeneous solution.

3. A 10 kg box rests on a frictionless surface. A horizontal force of 20 N is applied to the box. What is the box's acceleration?

A. 0.5 m/sÃ‚Â²
B. 1 m/sÃ‚Â²
C. 2 m/sÃ‚Â²
D. 10 m/sÃ‚Â²

Correct answer: C

Rationale: Use Newton's second law, F = ma, where F is the net force, m is the mass, and a is the acceleration. Since there is no friction, the net force equals the applied force (20 N). Therefore, a = F/m = 20 N / 10 kg Ã¢â€°Ë† 2 m/sÃ‚Â².

4. Which technology allows scientists to directly edit the human genome?

A. Polymerase Chain Reaction (PCR)
B. Gel electrophoresis
C. DNA sequencing
D. CRISPR-Cas9

Correct answer: D

Rationale: Rationale: A) Polymerase Chain Reaction (PCR) is a technique used to amplify a specific segment of DNA through repeated cycles of heating and cooling. PCR is not used for directly editing the human genome. B) Gel electrophoresis is a technique used to separate DNA fragments based on size. It is not used for directly editing the human genome. C) DNA sequencing is a method used to determine the precise order of nucleotides in a DNA molecule. While DNA sequencing is important for understanding genetic information, it is not used for directly editing the human genome. D) CRISPR-Cas9 is a technology that allows scientists to make precise changes to the DNA of living organisms, including the human genome. CRISPR-Cas9 works by guiding the Cas9 enzyme to a specific location in the genome where it can make targeted cuts or edits. This technology has revolutionized genetic research and has the potential for applications

5. A scientist observes a new species of bird with uniquely shaped wings. They hypothesize that the wing shape allows for superior gliding ability. Which observation would most strongly support this hypothesis?

A. The bird is found in mountainous regions.
B. The bird has feathers with low friction.
C. The bird can fly long distances without flapping.
D. The bird's wing muscles are stronger than other birds.

Correct answer: C

Rationale: Direct observation of gliding ability directly tests the hypothesis about the wing shape's function. Other observations might be relevant but provide less direct evidence.

6. She finds out that some managers have benevolent-authoritative style of management. Which

A. Have condescending trust and confidence in their subordinates
B. Gives economic or ego awards
C. Communicates downward to the staff
D. Allows decision making among subordinates

Correct answer: D

Rationale: The correct answer is D because the benevolent-authoritative style of management involves allowing decision-making among subordinates. This style combines a caring attitude towards employees with a level of authority and control. Managers who adopt this style often empower their subordinates to make decisions within a set framework, fostering a sense of autonomy and responsibility among the team. Options A, B, and C do not accurately describe the characteristics of a benevolent-authoritative management style, making them incorrect choices for this question.