Biology 1305 Chris Lopez (Baylor): Mini Exam 1 ch. 1-5

biology

the scientific study of life

Organization- Information- Energy and Matter- Interactions- Evolution

5 themes of biology

Reductionism

an approach that reduces complex systems to simple components that are manageable to study

Emergent properties

result from the arrangement and interaction of parts ascomplexity increases

eukaryotic cell

has membrane-enclosed organelles, the largest of which is usually the nucleus

prokaryotic cell

simpler and usually smaller and does not contain a nucleus or other membrane-enclosed organelles

Genes

are the units of inheritance- They encode information for building the moleculeswithin the cell

Gene expression

is the process of converting information from gene to cellular product

Genomics

is the study of whole sets of genes in one or more species

negative feedback

where the response reduces the initial stimulus

positive feedback

where an end product speeds up its own production

Bacteria, Archaea, and Eukarya

Organisms are currently divided into three domains

Plants, Fungi, Animals, and Protists

Eukarya has four subgroups-

unequal reproductive success

Evolution occurs ------------ of individuals which leads to adaptation to their environment

Qualitative data

often take the form of recorded descriptions

Quantitative data

are expressed as numerical measurement, organized into tables and graphs

Inductive reasoning

Uses specific observations to construct general scientific principles- derives generalizations from a large number of specific observations

Deductive reasoning

uses general premises to make specificpredictions• Applies general principles to predict specific results• Used to infer the species of a specimen from its characteristics

never

We can ----- prove that a hypothesis is true

independent variable

is the one that is manipulated by the researchers

dependent variable

is the one predicted to be affected in response

atom

is the smallest unit of matter that stillretains the properties of an element

Protons

Positively charged particles• Located in the nucleus

neutrons

Neutral particles• Located in the nucleus

Electrons

Negatively charged particles• Found in orbitals surrounding the nucleus

atomic nucleus

Neutrons and protons form the

mass number

atomic mass ≈

number of protons + number of neutrons

mass number =

number of protons

atomic number =

Isotopes

are atoms of an element that differ in the number of neutrons

Ions

are charged particles - unbalanced atoms

Cation

- more protons than electrons = net positive charge

Anion

- fewer protons than electrons = net negative charge

orbital

is the three-dimensional space where an electron is found 90% of the time

Potential energy

is the energy that matterpossesses because of its location or structure

electron shells

Electrons are found in different ---------- each with a characteristic average distance and energy level

Octet rule

- atoms tend to establish completely full valence shells

Covalent Bonds (share electrons)

polar and Non-polar covalent bonds/electronegativity

Ionic Bonds (transfer electrons)

cation and Anions/opposite charges attract

hydrogen bonds

Attraction between opposite partial charges

molecule

consists of two or more atoms held togetherby covalent bonds

single bond

is the sharing of one pair of valence electrons

double covalent bond

is the sharing of two pairs of valence electrons

Electronegativity

is an atom's attraction for the electrons in a covalent bond

ionic compounds or salts

Compounds formed by ionic bonds are called

Reactants

original (starting) molecules

Products

molecules resulting from reaction

polar

Water is a ---- molecule; the overall charge is unevenly distributed

Cohesive behavior

cohesion, surface tension, adhesion

Ability to moderate temperature

High specific heat, high heat of vaporization

ice floats

Expansion upon freezing

Acids and bases

Versatility as a solvent (water)

Cohesion

results in high surface tension, a measure of how difficult it is to stretch or break the surface of a liquid

Adhesion

is an attraction between different substances, for example, between water and plant cell walls

Kinetic energy

is the energy of motion

calorie (cal)

is the amount of heat required to raise the temperature of 1 g of water by 1 C

high specific heat

the --------- of water minimizes temperature fluctuations to within limits that permit life

solution

is a liquid that is a completelyhomogeneous mixture of substances

solvent

is the dissolving agent of a solution

solute

is the substance that is dissolved

hydrophilic (ionic and polar)

substance is one that has an affinity for water

hydrophobic (non polar)

substance is one that does not have an affinity for water

Molecular mass

is the sum of all masses of all atoms in a molecule

increase, decrease

Acids ------ hydrogen ion concentration

Bases ------ hydrogen ion concentration

less than 7

Acidic solutions have pH values...

greater than 7

Basic solutions have pH values...

Buffers

are substances that minimize changes in concentrations of H+ and OH- in a solution

Organic chemistry

is the study of compounds that contain carbon,regardless of origin

four covalent bonds

With four valence electrons, carbon can form---------- with a variety of atoms

hydrogen, oxygen, and nitrogen

The most frequent bonding partners of carbon are

Hydrocarbons

are organic molecules consisting of only carbon and hydrogen

Isomers

are compounds with the same molecular formula but different structures and properties

Structural isomers have different covalent arrangements of their atoms

------- isomers have different covalent arrangements of their atoms

Cis-trans

------isomers (also called geometric isomers) have the same covalent bonds but differ in their spatial arrangements

Enantiomers

are isomers that are mirror images of each other

-OH (Hydroxyl group)

-CO (Carbonyl group)

-SH (Sulfhydryl group)

polar functional groups

-COOH (Carboxyl group)

-NH2 (Amino group)

-PO4 (Phosphate group)

Charged Functional Groups

-CH3 (Methyl group)

Non-Polar Functional Groups

polymer

A long molecule consisting of many similar building blocks (monomers).

Carbohydrates, proteins, and nucleic acids.

What are three examples of polymers?

dehydration reaction

occurs when two monomers bond together through the lossof a water molecule

hydrolysis

Polymers are disassembled to monomers by------ a reaction that is essentially the reverse of the dehydration reaction

Enzymes

are specialized macromolecules that speed up chemical reactions such asthose that make or break down polymers

Carbohydrates

Monomer: Monosaccharide

Polymer: Polysaccharide

Bond: Glycosidic bond

Function: Energy

phospholipid

two fatty acids and a phosphate group are attached to glycerol/The two fatty acid tails are hydrophobic but there is a hydrophilic head

protein

Monomer: Amino Acids

Polymer: Polypeptide

Bond: Peptide bond

nucleic acid

monomer: Nucleotide

Polymer: Polynucleotide

Bond: Phosphodiester Bond

Function: Info storage