Bio Exam 1

Chapter 1-3

What are the characteristics of living organisms?

1. Organized and composed of cells

2. Reproduce, grow, and develop

3. Respond to changes in their environment

4. Capture and produce/process energy

5. Adapt and evolve over time as a population

6. Have regulatory mechanisms at many different levels (hierarchy of life)

7. All information is genetically encoded (DNA)

Prokaryotic cells are ______ organisms

singlecelled

Eukaryotic cells can be ______ or ______ organisms.

single-celled or multicelled

The smallest component of life’s hierarchy is _____

molecules

Everything is made of _____, both living and non-living

atoms

Cells are the _______

basic unit of life

The smallest unit of an element that is still able to retain its properties is a(n) _____

atom

What are the elements that make up 96% of the human body? (The Big 4)

1. Oxygen (65%)

2. Carbon (18.5%)

3. Hydrogen (9.5%)

4. Nitrogen (3%)

The atomic number is equal to….

the number of protons

Protons and neutrons are found in the _____

nucleus

When an element’s electrons change, it is called an ____

ion

When an element’s neutrons change, it is called an _______

isotope

The mass number equals…

the number of protons plus the number of neutrons

Many isotopes are ______, meaning they are radioactive

unstable

_______ can be used in research, medical diagnosis, and treatment because they behave identically in chemical reactions

isotopes

The inner most shell is considered full with __ electrons

2

Outer shells are considered full with __ electrons

8

What does inert mean?

Unavailable/full. An atom won’t bond with other atoms

How are ionic bonds formed?

between charged atoms, and typically with metals and nonmetals

After an ion donates an electron, the two ions are positively and negatively charged, and _____ each other, forming a compound.

attract

Ionic bonds have _____ strength. When they are in dry environments, the bond is ______. When ionic substances are in water, the bond is _____.

moderate; strong, weak

Salts are held together by _____ bonds

ionic

Sugars are held together by _____ bonds

covalent

What is an example of an ionic compound?

sodium chloride

sodium atom + chlorine atom = sodium and chloride ions

sodium ion + chloride ion = sodium chloride

What is represented in this image?

Sodium Chloride

How are covalent bonds formed?

when two atoms share electrons

(co=together, sharing)

Covalent bonds are the _____ bond

strongest

Rather than donate or gain electrons, atoms with covalent bonds ______ electrons

share

Nitrogen has 5 valence electrons. How many bonding partners/covalent bonds can it have?

3

Nonpolar =

shared equally

Polar = 

shared unequally

What is it called when an atom is large and tends to grab electrons close to itself?

electronegativity

Water is _____; aka formed by ______ bonds

polar; polar covalent

A dashed line on a model indicates a ________

hydrogen bond

A solid line on a model indicates a _______

covalent bond

What are the properties of water?

1. High Heat Capacity/Evaporation

2. Good Solvent

3. Cohesion and Adhesion

4. High Surface Tension

5. Low Density as a Solid

Acids have more ____ ions and less ____ ions

H+ (hydrogen), OH- (hydroxide)

Bases have more ____ ions and less ____ ions

OH- (hydroxide), H+ (hydrogen)

What is an example of a covalent compound?

Water

What is this?

Amino acid

What is this?

Nucleotide

Amino acids are held together by _____

peptide bonds

What is a disease related to misfolded proteins?

Mad Cow Disease

Water has high surface tension because of its _____ ability

cohesion

Why does water have a high heat capacity?

Energy from the sun breaks the hydrogen bonds but they replace themselves quickly

Inorganic molecules have ____ atoms and are held together by _____ bonds

fewer; ionic

Organic Molecules have _____ atoms and are held together by ______ bonds

many; covalent

Inorganic molecules are usually associated with _____ organisms/matter

nonliving 

Organic molecules are usually associated with _____ organisms/matter

living

Organic molecules always contain which two elements?

carbon and hydrogen

the tertiary structure of a protein refers to…

the overall three-dimensional structure

How do plants store energy for later?

starch

Hydroxyl group =

—OH

Carbonyl group =

>C=O

Carboxyl group =

— COOH

Amino group =

— NH2

Hydroxyl groups are found in

carbohydrates

Carbonyl groups are found in

lipids

Carboxyl groups are found in

proteins

Amino groups are found in 

proteins

Phosphate groups are found in 

DNA, ATP

What are isomers?

Compounds that have the same chemical formula but a different shape/function

What is an example of two isomers?

Glucose (6 membered ring) and fructose (5 membered ring)

What monomers make up lipids?

glycerol and fatty acids

What monomers make up carbohydrates?

Monosaccharides (simple sugar monomers)

What monomers make up nucleic acids?

nucleotides

Carbohydrates provide _____ and _____ energy

structure; quick (ex:bread, milk)

Which macromolecule regulates cell processes, forms bones and muscles, and transports materials

proteins (ex: eggs)

Which macromolecule provides long-term energy, forms membranes, and acts as a chemical messenger

Lipids (ex: butter)

What is starch’s function?

An energystorage unit for plants

What is glycogen’s function?

An energy storage unit for animals

What is dextran’s function?

An energy storage for bacteria

What is cellulose’s function?

Provides structure (cell wall of plants)

What is chitin’s function?

exoskeleton of various arthropods and cell walls of fungi

What is peptidoglycan’s function?

cell walls of bacteria

What are protein’s functions?

Structure, protection, regulatory, contractile, transport, storage, and enzymes

What is an example of structural protein?

keratin (fingernails, hair)

What is an example of a protective protein?

the antibodies that our white blood cells secrete

What is an example of a regulatory protein?

insulin

What is an example of a contractile protein?

actin

what is an example of a transport protein?

hemoglobin

What is an example of an enzyme protein?

amylase

what is an example of a storage protein?

albumin

Lipids are fats, ______ (polar/nonpolar), ______ (hydrophobic/hydrophilic)

nonpolar; hydrophobic

What are the components of a triglyceride molecule? 

glycerol head, fatty acid tails

Saturated fats are ____ at room temp, while unsaturated fats are ____ at room temp

solid; liquid

What is ATP?

adenine triphosphate

What are sterols?

component of plasma membrane, and sex hormones

what are waxes?

protection, prevent water loss