BIO 1320 Exam #1 Review

In an atom, each individual electron orbital (not energy level) may contain up to ______ electrons.

2

T/F: A substance with a pH of 3.7 would be considered a base, or "alkaline."

False; a pH below 7 is considered an acid, while a pH above 7 is considered a base.

T/F: Scientific theories are considered facts and therefore cannot be found false.

False; any theory may be proven false if future data is found that doesn't support it.

T/F: Atoms are created or destroyed in chemical reactions.

False; atoms cannot be created or destroyed ever, so chemical reactions involve atoms breaking or forming bonds with other atoms to create new molecules or compounds.

T/F: In asexual reproduction, genes from parents are mixed to create an entirely new offspring.

False; in asexual reproduction genes only come from a single parent, and the offspring are virtually identical.

T/F: An electron orbital is the path around the nucleus that the electron follows.

False; it is a region where an electron is likely to be located.

T/F: The mass number of an atom is the total number of protons, neutrons, and electrons.

False; it is just the total number of protons and neutrons since electrons are so small.

T/F: Water is sometimes called the "universal solute."

False; it's known as the "universal solvent" because it dissolves a wide variety of substances.

T/F: In asexual reproduction, 2 parents are required.

False; only 1 parent is required for asexual reproduction.

T/F: Salt dissolves in water because water causes the NaCl crystal to evaporate.

False; salt dissolves in water because polar water molecules surround Na+ and Cl- ions.

T/F: Unsaturated fatty acids contain more hydrogen than saturated ones.

False; saturated fatty acids contain more hydrogen.

T/F: Scientific theories are narrower in scope than hypotheses.

False; theories are generally broader in scope and can encompass multiple hypotheses.

What ion dissolved in water is critical to the function of molecules and is called a proton?

H+ (hydrogen ion)

T/F: Biologists ask questions about the natural world & living things.

True

T/F: In asexual reproduction, offspring are virtually identical to each other.

True

T/F: Scientific theories are supported by a large body of evidence.

True

T/F: The pH scale ranges from 0-14.

True

T/F: Carbohydrates are organic molecules that include sugars.

True.

T/F: The atomic number of an atom is smaller than its mass number.

True.

T/F: Water expands as it freezes because the hydrogen bonds in ice are stable and "lock" into a more widely-spaced array.

True.

T/F: Water regulates temperature.

True.

In an experiment, what is a variable defined as?

a changeable element of the experiment

What is a consumer?

a heterotroph that obtains energy & nutrients by eating other organisms

What is a decomposer?

a heterotroph that obtains energy & nutrients from wastes & dead organisms

A(n) ______ is an inherited characteristic or behavior which enables an individual to survive better than without the inherited characteristic.

adaptation

Flowers shaped for their pollinators, specific camouflaged color patterns of animals, and a beaver's enormous front teeth for gnawing are all examples of ________.

adaptations

A protein is an organic molecule with diverse functions and is composed of monomers called ______.

amino acids

What is a primary producer?

an autotroph that obtains energy & nutrients from nonliving sources

What is a single unit of an element?

atom

What are the levels of biological organization in a single multicellular organism, from smallest to largest?

atom -> molecule -> organelle -> cell -> tissue -> organ -> organ system -> organism

Molecules consist of two or more chemically linked _______, which are the smallest "pieces" or units of elements.

atoms

Particles that make up molecules are called ______.

atoms

What are the small chemical units that can combine to form molecules?

atoms

What are some of the possible limitations of scientific studies?

biases of scientists, misinterpretation of results, & reluctance to accept unexpected conclusions

A level of biological organization called the _______ includes all parts of Earth and its atmosphere where life can survive.

biosphere

Pairs of weak acids and bases that resist change in pH are called _____.

buffers

What is an organic molecule with carbon, hydrogen, and oxygen in a 1:2:1 proportion?

carbohydrate

______ are one of the four most abundant types of organic molecules in organisms and consist of carbon, hydrogen, and oxygen often in a proportion of 1:2:1. These organic molecules include monosaccharides and polysaccharides.

carbohydrates

Organic molecules are defined as chemical compounds that contain both ______ and hydrogen.

carbon

What is the basic unit of life and consists of a membrane enclosing water, DNA, and other chemicals?

cell

What is the smallest unit of life?

cell

In the hierarchical organization of life, tissues are a collection of specialized ______ functioning in a coordinated way.

cells

What is evolution?

changes in genetic makeup of a population over multiple generations

When the bonds of two or more molecules are broken and new ones formed, this is called a _____.

chemical reaction

The group in an experiment that is untreated and provides a basis for comparison is called the ______.

control or control group

What type of bond involves two atoms sharing electrons which travel around both nuclei?

covalent

Ice cubes float in a glass of water because ice is less _____ than liquid water.

dense

What is a pure substance that cannot be broken down by chemical means into other substances?

element

Darwin and Wallace used the theory of ______ to hypothesize that a very long-tongued insect must exist that can pollinate flowers of the Angraecum sesquipedale on Madagascar.

evolution

Hypotheses are often tested with an investigation called a(n) ______.

experiment

In the scientific method, a(n) ______ is an investigation carried out under controlled conditions to test a hypothesis.

experiment

In ecosystems, organisms that eat other organisms are called consumers, or _________.

heterotrophs

What describes the state of internal constancy maintained by an organism?

homeostasis

A _____ bond occurs when atoms with opposite partial charges attract each other.

hydrogen

A(n) _____ bond forms between a hydrogen atom with a partial positive charge on one molecule and another atom, such as oxygen, with a partial negative charge on an adjacent molecule.

hydrogen

Living organisms require a large temperature stimulus before the body temperature changes because the ______ bonds of water counteract molecular movement.

hydrogen

What type of bond forms between opposite partial charges on adjacent molecules or within a large molecule?

hydrogen

A type of chemical bond called a(n) ______ bond forms between atoms when one atom releases a valence electron to become a cation, and the other atom uses this electron to complete its own valence shell and becomes an anion.

ionic

What type of bond is formed from the attraction of two ions with opposite charges?

ionic

What type of organic molecule is a steroid?

lipid

What type of organic molecule is a triglyceride?

lipid

What type of organic molecule is hydrophobic because of its many nonpolar carbon-carbon & carbon-hydrogen bonds?

lipid

What group of organic molecules does not dissolve in water and does not consist of long chains of monomers?

lipids

The total number of protons plus neutrons for an atom equals the _____.

mass number

The total number of protons plus neutrons for an atom equals the ______.

mass number

Anything that takes up space is defined as _____.

matter

Paper, water, computers, and you are all forms of ______ because each of these items takes up space.

matter

Coastal regions of continents tend to have ______ climates than inland regions due to the stabilizing effects of steady ocean temperatures.

milder

Atoms can bond together to form ______.

molecules

One subunit of an organic molecule is called a ______.

monomer

Polymers, such as carbohydrates, proteins, and nucleic acids, consist of small subunits called ______ linked together to form long chains.

monomers

What process favors survival of specific individuals within a population based on inherited characteristics?

natural selection

_______ is a mechanism of evolution in which certain individuals from a population exhibit enhanced reproductive success based on inherited characteristics.

natural selection

Pure water has a(n) ______ pH.

neutral

What type of polymer is made up of many nucleotides?

nucleic acid

Nucleotides are the monomers of polymers called _______.

nucleic acids

What are the four steps of the scientific method, in chronological order?

observation -> hypothesis -> predictions & experiments -> data & conclusions

Compartments within cells that carry out specific functions are called _____.

organelles

What type of molecules are found in living things and contain both carbon and hydrogen?

organic molecules

What type of organic molecule is an enzyme?

protein

What type of organic molecule is composed of monomers called amino acids?

protein

What type of organic molecule is composed of monomers called amino acids?

proteins

A hydrogen ion (H+) has only one subatomic particle, a(n) ______.

proton

Water is the ______ in aqueous solutions because it can dissolve polar molecules.

solvent

Cohesion is the tendency of water molecules to _____.

stick to each other

Adhesion is the tendency of water molecules to _____.

stick to other molecules

What is the science of naming and classifying organisms?

taxonomy

In the hierarchy of biological organization, an organ is composed of several ______ interacting and working together.

tissues

Organs are made up of _______.

tissues

Many fungi, plants, bacteria, and animals produce toxic chemicals to _____.

ward off potential predators or competitors

What substance regulates temperature, dissolves many chemicals, and has cohesive and adhesive properties?

water