BIO 1107 test 1

reductionism

makes complex systems simpler but limits your view

emergent properties

new properties found at each level of organization

prokaryotic cells

single celled microorganisms

eukaryotic cells

has membrane inclosed organelles

gene expression

process of how info in a gene directs the making of a cellular product

genome

“library” of genetic instruction an organism inherits

genomics

studying sets of genes in one or more species

proteomics

study of sets of proteins and their properties

proteome

entire set of proteins shown by a cell tissue or organism

negative feedback loop

a response reducing the initial stimulus

positive feedback loop

an output speeding up its own production

evolution

press of biological change when species change from their ancestors over time making species different while some species share traits because of a common ancestor

data

recorded observations

hypothesis

explanation based on observation and assumptions that lead to a testable prediction

experiment

scientific test carried out under controlled conditions

variable

feature or quantity that varies in an experiment

independent variable

factor being controlled by researcher s

dependent variable

factor being measured and predicted to be affected by the independent variable

theory

much broader scope than a hypothesis

model organism

a species that grows in the lab and lends itself particularly well to the questions being investigated

matter

anything that takes up space and is composed of mass

element

substance that cannot be broken down

compound

substance consisting of two or more elements combined in a fixed ratio

essential elements

element an organism needs to live

trace elements

required by an organism in very very little quantities

atom

smallest unit of matter that still retains the properties of an element

atomic nucleus

where protons and neutrons are closely packed together in a dense core

dalton

unit of measurement for the mass of atoms with their subatomic particles

atomic number

all atoms of a particular element have the same amount of protons in their nuclei

mass number

total number of protons and neutrons

atomic mass

total mass of an element

isotope

different forms of the same element

radioactive isotope

in which the nucleus decays spontaneously giving off particles and energy

ha;f life

time it takes 50 percent of the parent isotope to decay

radioactive decay

scientist measure ratio of different isotopes and calculate how many half lives have passes since an organism was fossilized

energy

capacity to cause change by doing work

potential energy

energy matter possesses bc of its location or structure

electron shells

average distance from nucleus with a characteristic average distance and energy level

valence electrons

electrons in th outermost shell

valence shell

outermost electron shell

orbital

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

chemical bonds

atoms share or transfer valence electrons and result in atoms staying closer together

covalent bonds

sharing a pair of valence electrons by two atoms

molecule

two or more atoms held together by a covalent bond

single bond

a pair of shared electrons

double bond

when an atoms forms a molecule by sharing two pairs of valence electrons

valence

bonding capacity and usually equal to the number of electrons required to complete the atoms outermost shell

electronegativity

attraction of a particular atom for the electrons of a covalent bond

non polar covalent bond

two atoms of the same element in a covalent bond p

polar covalent bond

an atom is bonded to a more electronegative atom and the electrons of the bonds aren’t shared equally

ionic bond

attraction of an anion and cation

ionic compound

usually salt compounds formed by ionic bonds

hydrogen bond

when a hydrogen is covalently bonded to an electronegative atom

van der Waals interactions

when regions of positive and negative charge change so all atoms and molecules stick together

chemical reactions

making and breaking of chemical bonds leasing to changes in composition of matter

products

resulting materials

reactants

starting materials

chemical equilibrium

reactions are still going on in both directions but with no net effect on the concentrations of products and reactants

hydrogen ion

what is transferred when a H atom in a hydrogen bond between water molecules shifts from one molecule to the other and the hydrogen atom leaves its electron behind

hydroxide ion

the water molecule that lost a proton and is now a hydroxide ion

hydronium ion

the hydroxide ion bonds to another water molecule

acid

substance that increases the hydrogen ion concentration of a solution

base

substance that reduces hydrogen ion concentration.

PH

a number scale for expressing the range of hydrogen and hydroxide ions and defined by a negative logarithmic function

buffer

substance that minimizes changes in the concentration of hydroxide and hydrogen ions in a solution

ocean acidification

when ocean water ph drops because CO2 reacts and forms carbonic acid

organic chemistry

study of compounds containing carbon

carbon chain

series of covalently bonded atoms that forms structural framework of most oraninc molecules

carbon skeleton

chain or rings of carbon atoms that forms the backbone of an organic molecule

hydrocarbon

organic molecule consisting of only carbon and hydrogen

isomers

compounds that have the same number of atoms of the same elements but different structures and hence different properties

structural isomers

differ in covalent arrangements of their atoms

cis trans isomers

covalent bonds to the same atoms but atoms differ in spatial arrangements due to inflexibility of bonds

enantiomers

isomers mirror image of each other in shape due to presence of asymmetric carbon

functional groups

specific set up of atoms commonly attached to the carbo skeletons of organic molecules in chemical reactions

ATP

releases free energy when its phosphate bonds are hydrolyzed this energy is then used to drive endergonic reactions in cells

polymer

long molecule consisting of many similar or identical building blocks linked by covalent binds

monomer

repeating until that serve as the building blocks of polymers

macromolecules

giant molecule formed by the joining o smaller molecules

enzymes

specialized macromolecules that speed up chemical reactions

dehydration reaction

if water is lost when two molecules are covalently bonded

hydrolysis

process essentially reversing dehydration reaction or when the bad between monomers is broken by the addition of a water molecule

monosaccharides

smallest carbohydrate used as a monomer and generally have molecular formula C6H12O6

disaccharide

two monosaccharides joined by a glycosidic linkage

glycosidic linkage

a covalent bond formed between two monosaccharides by a dehydration reaction

starch

a polymer of glucose monomers

glycogen

a polymer of glucose hair is like amylopectin

cellulose

structural polysaccharide of. plant cell wall

chitin

structraul polysaccharide use day arthropods to build their exoskeletons

lipids

any group of large biological molecules that mix poorly if at all with water

fat

lipid consisting o three fatty acid tails linked with a glycerol molecule head

fatty acid

a carboxylic acid with a long carbon chain

ester linkage

bond between hydroxyl group and carboxyl group

saturated fatty acid

there are no double bonds between carbon atoms so a many hydrogen atoms as possible are bonded to the carbon skeleton

unsaturated fatty acid

has one or more double binds with one or fewer hydrogen atoms on each double bonded carbon

trans fat

an unsaturated fat formed artificially during hydrogenation of oils containing one or more trans double bonds

phospholipid

lipid made of glycerol ad two fatty acid chains and a phosphate group chins act non polar and heads polar

steroids

lipids characterized by a carbon skeleton consisting of four fused rings

catalysts

chemical agents that selectively speed up chemical reactions without being consumed in a reaction

protein

biologically functional molecule made pf one or more polypeptides each folded and coiled into a specific 2D structure