Biology 101 - Chapter 2 Smart Book

--- 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 polysacchaides.

Carbohydrates

True or False: Atoms are created and destroyed in chemical reactions

False

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

H +

An atom or group of atoms with a net negative charge or a net positive charge is called an ---

Ion

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 bond

Anything that takes up space is defined as

Matter

Select all of the following that are polymers, which are molecules composed of multiple monomers together.

- nucleic acid - polysaccharide -protein

Select all of the following substances that are hydrophobic and do not dissolve in water.

- olive oil - fats

Select all of the following that are represented by the number above each of the elements in the periodic table.

-atomic number - number of protons in that atom

Select all of the following that are elements

-carbon -oxygen

Select all of the following that are subatomic particles

-electron -proton -neutron

Use the period table, and select all of the following that are trace elements

-iodine (I) -boron (B) -Fluorine (F) -molybdenum (Mo)

Select all the reasons why water is essential to life.

-it dissolves a wide variety of substances - it plays a role in many chemical reactions - it regulates temperature

Select all the examples of chemical elements.

-oxygen -carbon -nitrogen -sodium -hydrogen

Rank the covalent bonds from weakest at the top to strongest at the bottom

-single covalent bond - double covalent bond -triple covalent bond

Match each arrow from the figure with the correct label

1 - electron 2- nucleus 3- proton 4- neutron

Rank the following in order from smallest mass to largest mass.

1. electron 2. proton 3. atom

If a chlorine (Cl) atom has a mass number of 35 and the atomic number shown on the periodic table ( which is 17), how many neutrons does the atom have?

18 35-17= 18 neutrons

Monosaccharides contain

5 or 6 carbon atoms

If an atom has an atomic number of 8 and a mass number of 16, then the atom has --- neutrons

8

The second energy shell of an oxygen atom can hold up to--- electrons because it contains 4 orbitals.

8

The first electron energy shell of an atom contains one electron orbital that can hold up to two electrons, and the second energy shell contains four electron orbitals that can hold up to --- electrons total.

8 electrons

What describes a hydrogen bond?

Atoms with opposite partial charges attract each other

Why does salt dissolve in water?

Polar water molecules surround Na+ and Cl- ions.

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

Proteins

Element

Pure substance that cannot be broken down by chemical means into other substances

To make a solution of lemonade, lemon juice and sugar are dissolved in water. The water is the ---- in this example.

Solvent

What is a correct description of hydrogen bonding among water molecules?

The partial positive charge of a hydrogen atom attracts the partial negative charge of an oxygen atom on an adjacent molecule

The outermost occupied electron energy shell of an atom is called the --- shell.

Valence shell

An electron orbital is

a region where an electron is liked to be located.

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

amino acids

Proteins are composed of monomers called

amino acids

Ion

are atoms which have gained or lost electrons

What is a single unit of an element?

atom

The number of protons in the nucleus is called the--- number of an element

atomic number

Two or more atoms are held together in a molecule or compound by attractive forces called chemical ---

bonds

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

carbon

What is an attractive force that holds atoms in a molecule together?

chemical bond

The property of water that produces water's surface tension is called ----, which is the tendency of water molecules to stick together.

cohesion

A peptide bond is a type of --- bond between amino acids.

covalent

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

covalent

The bonds holding together the hydrogen and oxygen atoms within a water molecule are called --- bonds, and the bonds between separate water molecules are called --- bonds.

covalent & hydrogen

A type of chemical bond called a(n) ---- bond occurs within a molecule when two atoms in a molecule share electrons, such as carbon and hydrogen in methane molecule pictured.

covalent bond

What is the process whereby a hydroxyl group (-OH) is removed from one molecule and a hydrogen ion (H+) from another molecule , bonding the two molecules together and forming a molecule of water?

dehydration synthesis

In a --- reaction, a covalent bond is formed between two monomers, and a molecule of --- is released.

dehydration, water

two monosaccharides joined by dehydration synthesis from a carbohydrate molecule called a ---

disaccharide

Sucrose and lactose are example of --- and are formed by joining two simple sugars.

disaccharides

What subatomic particles is located outside of the nucleus of an atom?

electron

If two atoms have the same atomic number, they are of the same --

element

The periodic table is a chart of ---- organized by their chemical properties.

elements

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

What type of chemical reaction is shown in the image?

hydrolysis

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

ionic

Matter

is any material that takes up space

Forms of a single element with different numbers of neutrons are called

isotopes

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

mass number

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

matter

When two or more atoms are chemically joined they form a(n)

molecule

One sub-unit of an organic molecule is called a

monomer

The smallest carbohydrates are called ---- and consist of a single monomer.

monosaccharides

Match the elements with their correct category using this picture of an abbreviated period table.

most abundant bulk elements- Hydrogen (H), carbon(C) trace elements- copper (Cu), Fluorine (F) less abundant bulk elements- Sulfur (S), magnesium (Mg)

The sum of the number of protons and the number of --- equals the mass number of an atom.

neutrons

An electron --- is an area around the nucleus of an atom where an electron is likely to be found.

orbital

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

organic

The valence shell of an atom is the

outer most shell

The --- table was invented by the Russian chemist Mendeleev and is shown in the picture.

periodic

A covalent bond where there is unequal sharing of electrons pairs is called a(n) ---- covalent bond.

polar

Description of a hydrophilic molecule

polar and readily dissolves in water

Proteins, nucleic acids, and some carbohydrates are large molecules called --, which consist of many monomers linked together.

polymers

Once a polypeptide or multiple polypeptides are folded into a functional shape, they are referred to as a(n)

protein

Match the subatomic particles with the correct charge

proton- positively charged neutron- uncharged electron- negatively charged

Atoms of the same element have the same number of

protons

The atomic number of an element is the number of

protons in the nucleus.

Another name for an unstable isotope is a(n)

radioactive isotope

Atom

smallest possible "piece" of an element that retains the characteristics of the element.

A --- is a substance dissolved in a solvent.

solute

To make lemonade solution, lemon juice and sugar are dissolved in water. The lemon juice and sugar are the --- in this example.

solutes

one or more solutes dissolved in a water solvent forms an aqueous --

solution

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

solvent

Cohesion is the tendency of water molecules to

stick together

Carbohydrates are macromolecules that include

sugars

Energy

the ability to do work and move matter

A --- covalent bond shares the highest number of electron pairs.

triple

In an atoms, each individual electron orbital (not energy level) may contain up to --- electrons

two electrons

Covalent bonds are broken within a polymer when a(n) --- molecule is added during hydrolysis.

water

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

water