General Biology - Midterm 1 Material (Lectures 1-6)

Biology and Learning, Scientific Process/Chemistry, Biological Molecules, Origin of Life, Cell Structure, Membranes & Transport

prediction

what you expect when you see result of hypothesis

theory

broad explanation with significant support

scientific method

observation, background, hypothesis, prediction, experiments, evaluation

- if wrong hypothesis: revise, repeat, verify

valence shell

outermost electron shell, where bonds form

electron shell

electron's state of potential energy

electronegativity

affinity for electrons, tendency of an atom to attract an electron (most EN are O, F)

chemical bonds

result from how atoms share electrons

energy

capacity to make change

molecules

compounds with 2 or more atoms

true

T/F: the farther away an e- is from the nucleus, the more potential energy the e- possesses

covalent bond

sharing electrons, codependent, strong bond

- can be polar (unequal sharing) or nonpolar (equal sharing)

- intramolecular

ionic bond

transfer/stealing of electrons, >2 diff in electronegativity

- the one that gains e- becomes the anion (-)

- the one that loses e- becomes the cation (+)

- intramolecular

nonpolar

same electronegativity, equal sharing of electrons

polar

van der waals

develop due to constant motion of e-, resulting in weak attractions between molecules

- temporary + and - sides

- intermolecular

- dipole-dipole and LDF

hydrogen bonds

really strong dipole-dipole interactions, stickiness between water molecules

- intermolecular

- hydrogen bonding with F, O, N

cohesion

water molecules stick to each other

adhesion

water sticks to other polar things

surface tension

the measure of how hard it is to break the surface of a liquid

- ex: some bugs can walk on water

water's high specific heat (and vaporization)

it is hard to change water temperature and state

- water is a stable environment

water expansion

water expands upon freezing, ice floats

- ice is less dense than liquid

water's versatility as a solvent

very versatile as a solvent due to its polarity, eventually dissolves all ions and many nonionic polar molecules

hydrophilic

attracted to water (polar)

- ions, salts

hydrophobic

aversion to water (nonpolar)

- ex: lipids

tetravalent

can form 4 bonds

- ex: carbon

organic compound

contain carbon bonded to H or C

- hydrophobic = insoluble in H2O

true

T/F: changing functional group changes function

hydroxyl

R-OH

polar, hydrophilic, neutral acidity

hydroxyl properties

carbonyl

R-CHO??

polar, hydrophilic, neutral acidity

carbonyl properties

carboxyl

R-COOH

carboxylic acid

if submerged in water, H+ is easily released

amino group

R-NH2

polar, hydrophilic, base

amino group properties

sulfhydryl

R-SH

polar, hydrophilic, slightly acidic

sulfhydryl properties

phosphate group

R-PO4H2

polar, hydrophilic, acid

phosphate group properties

methyl group

R-CH3

nonpolar, hydrophobic, neutral acidity

methyl group properties

monomers

building blocks of macromolecules

- joining these together creates polymers

(chain --> emergence)

lipids

which biological molecule is NOT a polymer

-ase

suffix for catalyst (ex: lactase breaks down lactose)

dehydration synthesis

reaction that links monomers together to make a polymer, removing water

dehydrogenases

enzymes used in dehydration synthesis

hydrolysis

adding a water and splitting a polymer into monomers

hydrolases

enzymes used in hydrolysis

neuronal development

- structure of nervous system determined by genes

- nervous system= neurons and supporting cells

- before birth (brain development and growth)

- gene expression how DNA is used

- signal transduction is when expression occurs

neuron

Nerve cell, excitable cell that transmit electrical signal

synapse

junction where neuron sends chemical signal to another, communication space

neuronal plasticity

- brain can modify connections based on experiences

- moldable or activity dependent

- occurs after birth

- neurons communicate and fire to learn/make memories (remembering = making neurons communicate again)

memories

long-lasting changes in the brain throughout life

- how often neurons talk to each other (remembering something/amount of activity at synapses) tells the brain what is important

- new experiences --> making connections

- practicing memories --> brain classifies as important

learning

the use of memory to lower likelihood of negative outcome

- application

memory

process where data/info is encoded, stored, and retrieved/recalled when needed

- storage

sensory memory

what you experience with senses

short term memory (or working memory)

what you are aware of now, held for a short time

long term memory

permanent connections in brain, unlimited

encoding

the processing of information into the memory system

- occurs from sensory memory to short term memory to long term memory

retrieval

the process of bringing to mind information that has been previously encoded and stored (from long term memory to short term memory)

long-term potentiation

persistent strengthening of synapses based on activity (long term firing)

- the process of improving memory retrieval

- increase in synaptic strength, a physical change in brain

- stronger signal = easier to recall

- not permanent, a long lasting increase in signal between 2 neurons

evolution

explains unity and diversity of organisms, with phylogenetic tree showing that we are descendants of a common ancestor, emerges at the population level

emergence

the whole is more than the sum of its parts

emergent properties

the new process that occurs when 2 things are put together in a certain way

levels of biological organization

organelle, cell, tissue, organ, organ system, organism, populations, communities, ecosystems, biosphere

observation

information obtained through the senses

law

statement of what always occurs in certain situations

hypothesis

a testable explanation for observations

polar, hydrophilic, acid

carboxyl properties

monomers

building blocks of macromolecules

polymers

joining monomers together yields ___ (chain leads to emergence)

monosaccharides (sugars)

monomers of carbohydrates

C6H12O6

glucose (linear/ring form) formula

• ring formed in 2 ways —> alpha or beta glucose

polysaccharides

polymers of carbohydrates (more than 2)

glycosidic linkage

covalent bond between monosaccharides

sucrose

glucose + fructose

lipids

which biological molecule does not form polymers?

hydrophobic

are lipids hydrophilic or hydrophobic?

phospholipid

lipid cell membranes with two fatty acid chains and one phosphate-containing group

polar, hydrophilic

head of phospholipid

nonpolar, hydrophobic

tail of phospholipid

energy storage

function of fats

glycerol (3 carbon alcohol with 3 OH), 1-3 fatty acids

lipids consist of

ester linkage

covalent bonds in lipids

triglyceride

storage form of fat, long-term energy access

amphipathic

having both hydrophobic and hydrophilic parts

• glycerol + 2 fatty acids (hydrophobic)

• phosphate group (hydrophilic)

phospholipid bilayer

hydrophobic tails on interior facing each other, hydrophilic heads on exterior

cholesterol

helps in the synthesis of most steroid hormones

• in animals, it aids in communication and cell membrane structure

proteins

made of amino acids

peptide bonds

covalent bonds between amino acids

polypeptide

sequence of 3 or more amino acids

• each amino acid bound to next with peptide bonds

true

T/F: polypeptide chain must be folded into correct 3D shape to become a protein

primary structure

sequence of amino acids joined by peptide bonds in polypeptide chain, determined by DNA

secondary structure

in single polypeptide, Hydrogen bonds stick amino acids together between amino group and carboxyl

• R groups do not participate

• alpha helix = coil

• beta pleated sheet

• folding primary brings this

tertiary structure

within single polypeptide, R-groups interact, folds into particular 3D shape

• folding secondary

• ionic and all bonds

quaternary structure

fitting tertiary structures together, multiple polypeptide chains form 1 macromolecule

• does not involve folding

• has all bonds

denaturation

loss of a protein’s 3rd or 4th structure

• this protein is now biologically inactive

• unfolding loses structure and thus also function

• can be caused due to changes in pH, salt concentration, and temperature

nucleotides

monomers of nucleic acids

DNA + RNA

deoxyribonucleic acid + ribonucleic acid

• transmit hereditary information

• determine protein production

phosphodiester bonds

nucleotides held together with