BIOLOGY EXAM 1

Water is the lightest (least dense) when it

Freezes

Which property of life does a virus possess?

Has order

Why does sweating cool your skin on a hot, dry day but makes you feel warmer on a hot, humid day?

Humidity keeps the sweat from evaporating as easily.

Individual water molecules are held to one another by relatively weak ----bonds.

Hydrogen

If the number of protons in an atom does not match the number of electrons, the atom is specifically called an

Ion

A recent commercial advertised for a wristband that claimed to restore health and balance by taking advantage of natural frequencies of your biofield. It even showed several people struggling to balance first without the wristband and then balancing fine with the wristband. For only $20 plus shipping and handling this device can be yours. Why should you be skeptical of the claims made in this ad?

It was not a controlled experiment

What is the sum total of all the chemical reactions that take place in your body called?

Metabolism

Darwin was not the first to propose that organisms evolve. Rather, the proposed a novel idea of what mechanism caused organisms to change over time. By what means did he propose that organisms evolve?

Natural Selection

is a virus alive

No, it does not possess all the requirements for life

What is typically the first step in the scientific method?

Observation

What is the most common element in your body?

Oxygen

Lipids are all hydro------.

Phobic. (Hydrophobic)

Water "beads up" on synthetic fabric like polyester but binds to cotton. What is the most likely explanation for this?

Polyester is nonpolar, whereas cotton is polar.

What should one do if the results of the experiment consistently do not support the original hypothesis?

Reject the original hypothesis and formulate a new hypothesis

Energy flows through an ecosystem. What is typically the originating source of energy in an ecosystem?

Sun

All living things require substantial quantities of carbon. Where do plants get the carbon they need to survive?

The air

Identify the part of an atom that most determines the chemical reactivity of an atom.

The electrons

What gives an amino acid it's unique chemical properties?

The side group

Why is one side of a water molecule partially negative while the other is partially positive?

Uneven sharing of electron pairs occur due to the strong pull of oxygen.

Could the scientific method theoretically be used to answer the question, does throwing a virgin into a volcano prevent it from erupting?

Yes, but only if it can be tested enough. You would need several virgins and volcanoes in the exact same environment.

The symbol for gold from the periodic table of elements is Au. Pure gold consists entirely of this element. How long could you repeatedly cut a kilogram of pure gold in half until the portion remaining, is split, would then no longer display the chemical properties of gold?

You could do this until you have a single ATOM remaining.

The difference in pH units between two acidic solutions is three. How much more acidic is the stronger acid than the weaker acid?

1,000 times more acidic

How many neutrons in a carbon-14 atom?

6

The typical carbon atom is described in the periodic table by the accompanying box. How many protons are in a typical carbon atom?

6

While the maximum number of electrons required to fill the outermost shell of an atom varies depending on the size of the atom, almost all the smaller atoms (2-20) are considered stable when they contain ------ electrons in the outermost shell.

8

What does the term theory mean to a scientist?

A collection of accepted hypotheses that explain a wide range of natural phenomena

In chemical bonding, when the bonded atoms share electrons, it's specifically called

A covalent bond

A population consists of

A group of interacting individuals of one species

The scientific method is

A rough recipe for answering questions, but the steps need not be performed in the same order as outlined nor must every step be performed at the same time

What is a trace element?

An element that is required in minuscule amounts for life

If you were able to combine all of the ecosystems on the planet, including the planet itself, you would have the

Biosphere

How do buffers minimize change in the pH of biological systems?

By BOTH absorbing H+ ions when there is an excess, and donating them when there is a shortage.

Which one is not one of the four atoms that make up the bulk of living organisms?

Calcium

The chemical name for table salt is sodium chloride, or NaCl. What type of chemical is NaCl?

Compound

The gasoline that fuels a car has substantial amount of energy inside of it. What was the original source of that energy?

Decaying plants and animals

The breaking of a large organic molecule into smaller individual subunits involves multiple ----------- ----------- reactions.

Dehydration synthesis

A college campus including the students, birds, trees, sidewalks, and air--makes up one complete

Ecosystem

Proteins are diverse molecules that perform a wide variety of functions. Which of the following is not a typical function of proteins?

Energy storage