Free Natural Science CLEP Question and Answers — Questions and Answers
Question 1: As inert gases, Nobel gases do not readily react. This is due to
- Their number of neutrons is equal to number of protons (Correct answer)
- They have 8 electrons in the valence shell
- They are diatomic
- All gases are inert
Correct answer: Their number of neutrons is equal to number of protons
Noble gases are inert because they possess a full outer electron shell (valence shell), typically with eight electrons (octet rule, or two for helium), making them exceptionally stable and unreactive. This stable electron configuration means they have no tendency to gain, lose, or share electrons in chemical bonds. While the provided answer A refers to the balance of protons and neutrons, this aspect relates to nuclear stability and isotope characteristics, not the chemical inertness of an atom.
Question 2: Which of the following is not found in animal cells but is present in plant cells?
- Cell membrane
- Cytoplasm
- Cell wall (Correct answer)
- Nucleus
Correct answer: Cell wall
Plant cells are distinguished from animal cells by several unique structures, most notably the cell wall. The cell wall is a rigid outer layer that provides structural support, protection, and maintains the cell's shape, a feature absent in animal cells. Both plant and animal cells possess a cell membrane, cytoplasm, and a nucleus.
Question 3: A measure of an electric charge is a
- Amperes
- Coulombs (Correct answer)
- Volts
- Ohms
Correct answer: Coulombs
A Coulomb (C) is the standard unit of electric charge in the International System of Units (SI). It quantifies the amount of electricity transferred by a constant current of one ampere in one second. Amperes measure electric current, Volts measure electric potential difference, and Ohms measure electrical resistance.
Question 4: Plant ovaries form as they develop.
- Embryo
- Seeds
- Fruit (Correct answer)
- Pollen
Correct answer: Fruit
In flowering plants, the ovary is the part of the pistil that contains the ovules. After successful fertilization, the ovules develop into seeds, and the surrounding ovary wall matures and ripens into a fruit. The fruit's primary biological function is to protect the developing seeds and facilitate their dispersal.
Question 5: An element's isotopes differ in the number of
- Protons
- Electrons
- Shells
- Neutrons (Correct answer)
Correct answer: Neutrons
Isotopes are atoms of the same element that share the same number of protons, which defines their atomic number and chemical identity. However, isotopes differ in their number of neutrons, leading to variations in their atomic mass. This difference in neutron count is the defining characteristic that distinguishes one isotope from another.
Question 6: Which of the following distinguishes allopatric speciation from sympatric speciation?
- Natural selection
- Genetic mutation
- Geographical isolation (Correct answer)
- All of the above
Correct answer: Geographical isolation
Allopatric speciation occurs when populations of a species become geographically separated, preventing gene flow and leading to independent evolutionary paths. In contrast, sympatric speciation occurs when new species arise within the same geographical area, often due to factors like polyploidy or disruptive selection. Therefore, geographical isolation is the key distinguishing factor between these two modes of speciation.
Question 7: The adipose tissue stores which of the following?
- Glycogen
- Fats (Correct answer)
- Proteins
- Iron
Correct answer: Fats
Adipose tissue, commonly known as body fat, is a specialized connective tissue primarily composed of adipocytes. Its main physiological function is to store energy in the form of lipids (fats), which can be mobilized and utilized by the body as fuel. Adipose tissue also plays roles in insulation, organ cushioning, and hormone production.
Free Natural Science CLEP Question and Answers
As inert gases, Nobel gases do not readily react.
This is due to