BIO 201 Quiz #1

What are the three subatomic particles that make up an atom?

Protons, neutrons, and electrons

What are the charges of the three subatomic particles?

Protons have a positive (+) charge, neutrons have a neutral charge, and electrons have a negative (-) charge

What is the mass of protons, neutrons, and electrons?

Protons and neutrons each have a mass of 1, while electrons have a mass of 0

Where are the subatomic particles located in an atom?

Protons and neutrons are in the nucleus, and electrons are in a cloud surrounding the nucleus

What does the atomic number of an element represent?

The number of protons in its nucleus

How many electrons can the first, second, and third shells hold?

The first shell holds 2, and the second and third holds 8

What condition makes an atom stable and unreactive?

When the outer electron shell is full

Why do atoms form chemical bonds?

To achieve a full outer electron shell and electrical neutrality

What is an ionic bond?

A bond formed when atoms or molecules with complementary opposite charges completely give up or receive electrons

What is the difference between a cation and an anion?

A cation is a positively charged ion and an anion is a negatively charged ion

What is a non-polar covalent bond?

A bond where electrons are shared equally between atoms

What is a polar covalent bond?

A bond involving unequal sharing of electrons because one atom is more electronegative

What is a hydrogen bond?

A very weak bond formed between the partial opposite charges of polar molecules

What is the central theory of biology?

Evolution

What happens at each new level of biological organization?

New properties emerge

What is the basic unit of life?

The cell

What molecule is the basis for the continuity of life?

DNA

How do organisms interact with their environment?

By exchanging matter and energy

What is correlated at all levels of biological organization?

Structure and function

What mechanisms regulate biological systems?

Feedback mechanisms

What are the properties of life?

Order

What is an ion?

An atom or molecule with a net charge resulting from the loss or gain of electrons

Define a cation.

An ion with a positive (+) charge

Define an anion.

An ion with a negative (-) charge

What is a scientific hypothesis?

A tentative explanation for an observation that is consistent with known facts and is both testable and falsifiable

Define a scientific theory.

A generalized hypothesis supported by considerable evidence that has been tested many times and never rejected

What is the difference between independent and dependent variables?

The independent variable is manipulated by researchers while the dependent variable is the one predicted to be affected in response

What is the purpose of a control group?

It provides a baseline for comparison against the experimental group to ensure results are due to the variable being tested

How do ionic bonds form?

They form through the complete transfer of electrons between atoms

What is the difference between polar and non-polar covalent bonds?

Non-polar bonds involve equal sharing of electrons while polar bonds involve unequal sharing

Why are hydrogen bonds important?

They are weak attractions between partial opposite charges that are of major importance in macromolecules

Why is molecular shape crucial in biology?

Shape determines function and allows molecules like morphine to fit into specific brain receptor