AP Biology unit 1.1 and 1.2 study guide

which property of water allows dogs to cool themselves by panting

waters' high heat of vaporization

Solvent

A liquid substance capable of dissolving other substances

polymer

A long molecule consisting of many similar or identical monomers linked together.

surface tension

A measure of how difficult it is to stretch or break the surface of a liquid

monomer

A simple compound whose molecules can join together to form polymers

Base

A substance that decreases the hydrogen ion concentration in a solution.

Acid

A substance that increases the hydrogen ion concentration of a solution.

enzyme

A type of protein that speeds up a chemical reaction in a living thing

Macromolecules

A very large organic molecule composed of many smaller molecules

Why does water have a high specific heat?

a water molecule can maek 4 hydrogen bonds

which property of water allows a paper towel to pick up a puddle of water

adhesion of water molecules to other kinds of molecules

which statement is true of water's tensile strength

it results from hydrogen bonding, helps water through plants, involves cohesion and adhesion

the temperature of boiling water remains constant because

it takes energy to break hydrogen bonds

covalent bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

dehydration synthesis

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.

polar covalent bond

A covalent bond in which electrons are not shared equally

Look at the figure showing the pH values of some familiar aqueous solutions. What is the difference between H+ concentration in an acidic solution such as lemon juice (pH 2) and a basic solution such as household bleach (pH 13)?

The H+ concentration of lemon juice is higher than the H+ concentration of household bleach by a factor of 1011 (100 billion).

heat of vaporization

The amount of energy required for the liquid at its boiling point to become a gas

specific heat

The amount of energy required to raise the temperature of 1 gram of a substance by 1 degree celcius

The unequal sharing of electrons within a water molecule makes the water molecule _____.

polar

what bond is found between oxygen and hydrogens

polar covalent

why amphipathic molecules line up at a water surface?

polar groups attract one another

cohesion

the atrraction between like molecules

Hydrolysis

the chemical breakdown of a compound due to reaction with water.

functional groups

the components of organic molecules that are most commonly involved in chemical reactions

heat capacity

the number of heat units needed to raise the temperature of a body by one degree.

electronegative

the tendency to attract electrons to form a chemical bond

interactions between atoms that result in polar covalent bonds

two atoms of different electronegativity share two electrons unequally

relate the heat capacity of water to the ability of organisms to maintain internal temperature

water has a high specific heat capacity, high amounts of energy are needed to break H bonds and change temp of water

Describe the circumstances in which water may behave as a solvent vs. when water is not able to act as a solvent.

water is only able to dissolve hydrophillic and polar, can't dissolve hydrophobic and nonpolar substances

A dehydration reaction is the process in which __________.

water molecules are produced as a polymer is formed from monomers

why is ice less dense than liquid water

water molecules make hydrogen bonds at definite angles and cold molecules move less than warm molecules

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

adhesion

An attraction between molecules of different substances

Cohesion

Attraction between molecules of the same substance

what elements are found in macromolecules

CHNOPS

hydrocarbon

Compounds composed of only carbon and hydrogen

organic compound

Compounds that contain carbon

difference between ionic bonds and covalent bonds

Electrons are exchanged between atoms held together by an ionic bond, but they are shared between atoms held together by a covalent bond

ionic bond

Formed when one or more electrons are transferred from one atom to another

Why doesn't oil mix with water?

Polar molecules attract one another.

evaporative cooling

The process in which the surface of an object becomes cooler during evaporation, a result of the molecules with the greatest kinetic energy changing from the liquid to the gaseous state.

Hydrophobic

Water fearing

nonpolar covalent bond

a covalent bond in which the electrons are shared equally by the two atoms

dissolving is best described as

a mingling of molecules and/or ions.

Explain the importance of adhesion and cohesion to living systems.

allow for capillaru action and surface tension

The open spaces in water's crystal structure make it possible for ...

aquatic life to exist at the north pole

____ and ____ from the environment are necessary to build new molecules

atoms and molecules

importance of carbon atom as a building block of life over the other elements in biomolecules

can form covalent bonds to as many as four different atoms

The large diversity of shapes of biological molecules is possible because of the extensive presence of _____ in the molecules

carbon

the hydrogen bonds between water molecules result in ____ , ____, and ____ ____

cohesion, adhesion, surface tension

buffer

compound that prevents sharp, sudden changes in pH

What is another name for a condensation reaction?

dehydration

hydrophillic molecules

dissolve in water

why are hydrogen bonds weaker than covalent bonds

do not involve sharing of electrons

the tendency of an atom to pull electrons toward itself is referred to as its ___

electronegativity

how do organisms obtain raw materials to grow and live

food, water, oxygen, energy from other plants and animals

relationship bewteen the molecular structure of water and its properties of adhesion, cohesion, and surface tension and to the behavior of water as a solvent

form hydrogen bonds with other polar substanes, H20 molecules, resist disruption of surface when under sress, dissolve hydrophilic substances due ot its polarity

A water molecule can bond to up to _____ other water molecules by ____ bonds.

four... hydrogen

Explain the importance of buffers to biological systems.

help system maintain pH and constant environment

Because organisms are made primarily of water, they resist rapid temperature changes. This useful quality is based on water's _____

high specific heat

what bond is weaker

hydrogen

Water is a source of ______________ for chemical reactions in cells.

hydrogen and oxygen atoms

Water molecules have a polarity, which allows them to be electrically attracted to other water molecules and other polar molecules by weak chemical bonds known as _____.

hydrogen bonds

random collisions allow some molecules to accumulate more energy than other molecules. The weakness of the ________ lets those molecules escape, leaving the cooler ones behind.

hydrogen bonds

when you heat water, much of the heat is used to break _____

hydrogen bonds

Water has surface tension because ...

hydrogen bonds between surface water molecules resist being stretched

where does surface tensions result from

hydrogen bonds formed between water molecules at the surface and between

What is the name of the process during which a bond between two monomers is broken?

hydrolysis

_____ and _____ are used to cleave and form covalanet bonds between monomers

hydrolysis, dehydration synthesis

Describe the implications of the different densities of frozen vs. liquid water to aquatic ecosystems.

ice= less sense, floats above liquid water

in hydrolysis, water goes __ and energy comes _____

in, out

what happens with remaining heat after hydrogen bonds are formed

increases molecular motion raising temperature

An acid is a substance that _____.

increases the hydrogen ion concentration of an aqueous solution

organisms must exchange ____ with the environment to grow, reproduce, and maintain organizaiton

matter

the subcomponents of biological molecules and their sequence determine the properties of that ___

molecule

which factor is important in making it possible to cool yourself by sweating

molecules collide with varied angles and speeds and hydrogen bonds are relatively weak

phosphorus is used to build ___ and ___

nucleic acids and certain lipids

in dehydration synthesis, water goes ___ and energy goes ___ -

out, in

living systems depend on properties of water that result from its _____ and ______ ____

polarity, hydrogen bonding

nitrogen is used to build ____ and ____

proteins and nucleic acids

parts of an atom

protons, neutrons, electrons

surface tension

resistance of the liquid to stretching or breaking.

what is a buffer

solutions made of an acid/base pair that minimize the effects of increasing H+ or OH-

carbon is used to build biological molecules such as carbohydrates, proteins, liqids, and nucleic acids. Carbon is used in ______ _____ and cell formation in all organisms

storage compounds

polarity and hydrogen bonding capabilities of functional groups

when 2 equally strong atoms are bound, sharing of electrons will be equal. if functional group has an atom that has strong-weak bonds, group will be polar