Bio 2100 Exam 1

what gives an atom its identity

• the number of protons

if there is more electrons then protons then the atom will have a negative charge

electrons in the valence shell are more stable when they are in a pair

polar definition

• the unequal sharing of electrons

nonpolar

• when electrons are shared equally

what does a dashed line indicate

• a hydrogen bond

are hydrogen bonds or covalent bonds stronger

• covalent

how many electrons does each atom give in a covalent bond

• each atom gives one unpaired electron

what are DNA and RNA called

• nucleic acids

two nucleotides are linked with…

• a phosphodiester bond

  • a covalent bond

what are the subunits of a nucelotide

1. 5 carbon sugar

2. nitrogeneous base

3. phosphate group

where is the connection between two nucleotides happen

• on the phosphate group of one and the sugar of another

monomers are linked via covalent bonds to form polymers

are nucleic acids considered to be polar or nonpolar and why

• polar

  • because the phosphate group carries a charge

in which direction does dna run in

5’ to 3’

where can nucleotides only be added to (which end?)

3’

what is the primary structure of dna/a nucleic acid

• the sequence of nucleotides

what are DNA’s nucleotide bases

• cytosine

• guanine

• adenine

• thymine

what is similar about DNA and RNA primary structure

• has phosphodiester bonds

• 5’ to 3’ polarity

what is the difference between DNA and RNA primary structure

• uses uracil instead of thymine

• five carbon sugar is different

  • uses ribose instead of deoxyribose

what does RNA lack on the 2’ carbon

• an oxygen

what type of bonds are the bases held with

• hydrogen bonds

how many bonds does C and G have

• they have 3 hydrogen bonds

how many bonds does A and T have

• two hydrogen bonds

what represents DNA’s secondary structure

• helix

  • the primary is reading 5’ to 3’ of the bases

what is inside of DNA’s helix

• base pairs

what is outside DNA’s helix

• backbone

RNA secondary structure

• typically single stranded

• but can fold back in on itself to make a stem and loop structure to become double stranded

• usually short

• less extensive

what is the signficiance of the OH on the 2’ carbon on RNA

• it makes it more reactive meaning less stable

  • making DNA more stable

DNA kinda sits there until it is needed to make mRNA but RNA is always out and about

histogram

• frequency distributions

functions of proteins

• catalysis

• transporting materials

• cell signaling

• movement

• cell structure

• defense

what part of the amino acid acts as a base

• the amino group

what part of the amino acid acts as an acid

• carboxyl group

what is bonded to a central carbon in an amino acid

• a hydrogen atom

• carboxyl group

• amino group

• r group

where do amino acids link when they want to bond

• on the carboxyl group of one and the amino group of the other

  • a covalent bond forms

• the h on the amino and the o on the carboxyl

hydrogen bonds are about the partial charges and covalent is about the sharing

3 types of R groups

• fully charged

• partially charged

• not charged

sufyhydl

• S-H

  • can be present at the bottom of the R group

• and can make disulfide with another protein

an if then hypothesis is like

• cause and effect

  • if = cause

  • then = effect

another word for dependent variable

• outcome variable

what gives an amino acid polarity

• when it links together and there are two different structures at the front and back

primary structure of amino acids

• the linking

where are amino acids added to

• the carboxyl end

what direction is amino acids written in

• amino to carboxyl end

what bonds do peptide bonds have characterisitcs of

• a double bond

  • rigid

  • linear

  • more stable

a peptide bond is added to each N-C-C sequence

what types of bonds are used in protein secondary structure & which atoms

• hydrogen bonds on the backbones

• O of the carboxyl and H of the amino

• it gives the secondary structure support

what sticks out in amino acids secondary structure

• the r groups

teritary structure of amino acid and the bonds within

• hydrogen bonds on n-h and co in peptide backbone and r groups

• ionic bonds between full charges on r groups

• covalent bonds between suflur atoms in r groups

• interactions of hydrophobic r groups

• what helps it stay folded

peptide bond

• a carboxyl and amino group

3 domains of cellular life

• eukarya

• archea

• bacteria

what does every cell have

• cell membrane

• cytoskeleton

• genetic mateerial

• ribosomes

where is genetic material present

• chromosomes

ribosomes

• produce proteins

cytoskeletal elements

• tubular proteins

• structural support and transport materials

common cell elements

• organelles

• cell wall

• flagella

what is the cell wall made out of

• carbohydrates called cellulose

archean cells

• all single celled

• live in extremes

what supports archea to live in extreme environments

• unique carbs in their cell walls

• hydrocarbons in their membrane lipids

bacterial cells

• some are multicellular

• some have a cell wall and flagella

• most have singular, circular chromosome

Eukaryotic cells

• all have a nucleus

• mitrochondria

what are the two membranes of the nucleus

• nuclear envelope

• pores

  • that are in the nuclear envelope

  • control what goes in and out

what are prokaryotes

• archea and bacteria

what do eukaryotes and prokaryotes share

• cell membrane

• ribosomes

• chromosomes

• cytoskeletal elements

describe the flagella in bacterial and eukaryote

• bacterial it propels

• eukarya it goes and forth

  • some have cilia (which is smaller flagella)

do prokaryotes or eukaryotes outnumber the other

PROKARYOTES

what can create turgor pressure

• the vaculoes

  • and it can keep the plant upright

where does the ER origninate

• at the nuclear envelope of the nucleus

• in rough ER there are ribososmes attached

golgi

• near outermost part of the ER

• proteins are process and packed for shipment here

• not physically connected to each other

cytoskeletal elements in eukaryotes

• actin filaments

• intermediate filaments

• microtubules

actin filaments

• string of proteins

• stiffin membrane

intermediate filaments

• middle size

• structure support

microtubules

• hollow cylinders

• made up of alpha-tubulin and beta-tubulin protein subunits

bacteria and archea have cytoskeletal elements but with different proteins

the more surface area the more membrane available to work

data never PROVES a hypothesis

when you break and form covalent bonds you are doing a…

• chemical reaction

  • changes in covalent bonds

are covalent bonds disrupted by significant change in temp or ph

• no

  • because they are super strong

what are the proteins involved in chemical reactions

• enzymes

without an enzyme covalent bonds remain stable

why does DNA last so long

• because it is held together by covalent bonds

  • and doesn’t have that OH on its 2’ carbon making it reactive

non covalent associations don’t need…

• enzymes becaue they are NOT chemical reactions

covalent bonds are…

• chemical reactions'

  • because they are actually forming or breaking something new

why are noncovalent bonds not a chemical reaction

• because they are only attracted because of the partial charges and not physically creating something new

are covalent or noncovalent interactions depenedent on concentration

• noncovalent

noncovalent interactions are sensitive to..

• variation in temperature and pH

  • because they are weak interactions

noncovalent bonds have NO different molecules forming

why do covalent bonds form

• so they can get to the most stable state

why do some electrons share equally and others dont

• because of electronegativity

  • the increase of electronegativity means an increase in affinty (close connection)

why does an atom get a partial negative charge

• because it is offsetting the little positive charge it has

what is the order of electronegativity

• oxygen → nitrogen → carbon = hydrogen

  • oxygen has the greatest affinity

if you are either polar or nonpolar you are still…

• covalent

are ionic bonds sharing

• no

ions are more important than ionic bonds in bio

when we talk about how hard a bond is it is under physiological conditions and that is mostly in water

are ionic bonds easy to break

• yes

  • why they aren’t as important because H20 disrupts them easily

    • and in bio water is always used

H20 is polar covalent with partial charges and can disrupt full charges

noncovalent interactions

• ionic bonds

• hydrogen bonds

• hydrophobic interactions

hydrogen bonds are NOT covalent

• they just like each others opposite charge presence