1. Which structure helps regulate body temperature by constricting or dilating in response to temperature changes?

A. Sebaceous glands
B. Hair follicles
C. Sweat glands
D. Langerhans cells

Correct answer: C

Rationale: The correct answer is C: Sweat glands. Sweat glands play a crucial role in regulating body temperature by producing sweat that evaporates from the skin surface, cooling the body when it's hot. Sweat glands can constrict to reduce sweating in cooler temperatures and dilate to increase sweating when the body needs to cool down. Sebaceous glands are responsible for producing oil to lubricate the skin and hair follicles help in hair growth. Langerhans cells are immune cells in the skin. Therefore, sweat glands are the structure specifically involved in regulating body temperature through constriction and dilation in response to temperature changes.

2. Which type of white blood cell directly attacks and destroys pathogens like bacteria and viruses?

A. Neutrophils
B. Lymphocytes
C. Monocytes
D. Eosinophils

Correct answer: A

Rationale: The correct answer is A: Neutrophils. Neutrophils are a type of white blood cell that plays a crucial role in the innate immune response by directly attacking and destroying pathogens like bacteria and viruses. They are the most abundant type of white blood cell and are known for their rapid response to infections. Neutrophils work by engulfing and digesting pathogens through a process called phagocytosis. Lymphocytes (option B) are involved in adaptive immunity, producing antibodies and coordinating immune responses. Monocytes (option C) differentiate into macrophages and dendritic cells, playing a role in phagocytosis and antigen presentation. Eosinophils (option D) are primarily involved in combating parasitic infections and allergic reactions, not directly attacking bacteria and viruses.

3. Which term refers to the resistance of a liquid to flow?

A. Density
B. Viscosity
C. Surface tension
D. Boiling point

Correct answer: B

Rationale: Viscosity is the term that refers to the resistance of a liquid to flow. It is a measure of how thick or sticky a fluid is, and it determines how easily a liquid can flow. Density (A) is a measure of how much mass is contained in a given volume, surface tension (C) is the property of a liquid that allows it to resist an external force due to the cohesive nature of its molecules, and boiling point (D) is the temperature at which a liquid changes to a vapor.

4. What is the purpose of the spindle apparatus in cell division?

A. To separate sister chromatids
B. To move chromosomes to opposite poles of the cell
C. To form a new nuclear envelope around each daughter cell
D. To synthesize new DNA

Correct answer: B

Rationale: Rationale: The spindle apparatus is a structure composed of microtubules that plays a crucial role in cell division (mitosis and meiosis). Its main purpose is to ensure the proper separation and distribution of chromosomes to opposite poles of the cell during cell division. This process is essential for the formation of two genetically identical daughter cells in mitosis or four haploid daughter cells in meiosis. Option A is incorrect because the separation of sister chromatids specifically refers to the role of the kinetochore fibers within the spindle apparatus. Option C is incorrect because the formation of a new nuclear envelope occurs after the chromosomes have been properly segregated. Option D is incorrect because DNA synthesis does not occur within the spindle apparatus; it takes place during the S phase of the cell cycle.

5. What are the four main types of macromolecules that are essential for life?

A. Carbohydrates, lipids, proteins, and nucleic acids
B. Carbohydrates, proteins, fats, and vitamins
C. Minerals, vitamins, proteins, and fats
D. Carbohydrates, lipids, proteins, and hormones

Correct answer: A

Rationale: These four types of macromolecules are the building blocks of life and play essential roles in various cellular processes. Carbohydrates: Carbohydrates are the primary energy source for cells and provide structural support for cell membranes and other cellular components. They are composed of carbon, hydrogen, and oxygen atoms and are classified into monosaccharides (simple sugars), disaccharides (double sugars), and polysaccharides (complex sugars). Lipids: Lipids are a diverse group of molecules that include fats, oils, and waxes. They are composed of carbon, hydrogen, and oxygen atoms and are insoluble in water but soluble in nonpolar solvents. Lipids serve as energy storage molecules, provide insulation for cells and organs, and are essential components of cell membranes. Proteins: Proteins are complex molecules composed of amino acids linked together by peptide bonds. They are responsible for a vast array of cellular functions, including structural support, enzymatic catalysis,

6. Which of the following is NOT a characteristic of living organisms?

A. Made up of cells
B. Able to reproduce
C. Require energy
D. Non-motile

Correct answer: D

Rationale: Rationale: A) Made up of cells: All living organisms are composed of one or more cells. This is a fundamental characteristic of life as defined by cell theory. B) Able to reproduce: One of the key characteristics of living organisms is their ability to reproduce and pass on genetic information to offspring. C) Require energy: Living organisms require energy to carry out various life processes such as growth, reproduction, and maintenance of homeostasis. This energy is obtained through processes like metabolism. D) Non-motile: While some living organisms may be non-motile (unable to move on their own), movement is a common characteristic of many living organisms. Motility allows organisms to respond to their environment, find food, escape predators, and carry out other essential activities.