| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.09 |
| Score | 0% | 62% |
Generally, an atom has __________ negative electrons orbiting the nucleus as it does positive protons inside.
more |
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equal numbers of |
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fewer |
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double the number of |
An electron is a subatomic particle that orbits the nucleus of an atom. It carries a negative electric charge. Generally, an atom has the same number of negative electrons orbiting the nucleus as it does positive protons inside.
"The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This describes which of Newton's laws of motion?
second |
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first |
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fourth |
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third |
Newton's second law of motion states that The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object. This law basically means that the greater the mass of an object, the more force is needed to overcome its inertia.
Atoms of an element whose atoms can vary in the number of neutrons in their nucleus are called which of the following?
ions |
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isotopes |
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reactants |
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products |
The atomic mass of an element listed in the Periodic Table represents the average mass of a single atom of that element and is measured in atomic mass units (amu). This number is an average as some elements have isotopes with atoms that vary in their number of neturons and, therefore, differ in weight.
Within DNA, a variety of a particular gene is called a(n):
chromosome |
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allele |
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homozygous |
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heterozygous |
The gene is the base unit of inheritance and is contained within DNA. A gene may come in several varieties (alleles) and there are a pair of alleles for every gene. If the alleles are alike, a person is homozygous for that gene. If the alleles are different, heterozygous.
In the classification of life, which of the following is not a domain?
archaea |
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eukaryota |
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animalia |
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bacteria |
The broadest classification of life splits all organisms into three groups called domains. The three domains of life are bacteria, archaea and eukaryota.