b110 exam1

what are the characteristics shared by all living organisms?

genetic material (DNA/RNA), cells, homeostasis, growth and development, metabolism, order/organization, response to external stimuli, evolutionary adaptation

why are viruses technically not alive?

they cannot reproduce/replicate on their own, and they do not have their own metabolism

evolution

changes in the genetic structure of a population over time

natural selection

the process of a population becoming better adapted to its environment over time

what requirements must be met for natural selection to take place?

competition and overproduction, genetic variation, and heritable traits

what kind of atmosphere did the earth have originally?

a reducing atmosphere

reducing atmosphere

favors reactions that add electrons to chemicals, which is vital for creation of complex organic molecules

fossils

preserved remnants of organisms or whole organisms embedded in substances or areas where bacteria that leads to decomposition can't get to them

what is the best source of fossils?

sedimentary rock

relative dating

finding out if a fossil is older/younger than another, or its relative age due to its placement in, most commonly, sedimentary rock

absolute dating

finding the fossils age in years

radiometric dating

a form of absolute dating, using the percentage of radioactive isotope of a certain element left in the fossil to find its age

half life

the amount of time it takes for a radioactive isotope to decay to half of its original size

covalent bonds

sharing of electrons in a bond between 2 atoms, relatively strong

electronegativity

the level at which an atom attracts/holds electrons

polar bond

the result of atoms with differing electronegativities bonding

nonpolar covalent bond

atoms with similar electronegativity bond together and electrons are evenly shared

ionic bonds

bonds formed between atoms that are oppositely charged, held together by electrostatic connections

hydrogen bonds

weaker than covalent bonds, intermolecular attractions where hydrogen atoms are bonded to very small, electronegative atoms and are attracted to lone electron pairs in neighboring molecules

water is a good solvent, what does that mean?

it can dissolve many things, and thanks to being polar it can always dissolved things with a charge

hydrophilic

a molecule that readily dissolves in water

hydrophobic

a molecule that avoids water, resists dissolving

amphipathic

a molecule that has portions that are hydrophobic along with portions that are hydrophilic

what are the 4 macromolecules?

proteins, lipids, nucleic acids, and carbohydrates

polymer

a long chain of repeating molecular units (monomers)

monomer

a singular molecular unit that makes up polymers when in a chain

anabolic reaction

smaller molecules form larger molecules

dehydration synthesis

smaller molecules are bonded together to form a larger molecule, and an h2o molecule is removed at each bonding step

catabolic reactions

breaking down larger molecules into their monomer units

hydrolysis

catabolic reaction,

what is an example of monosacharides

glucose, fructose

what is an example of a polysacharide

starch, glycogen

what are the monomers of proteins

amino acids

what are the monomers of nucleic acids

nucleotides

nitrogenous base

a ringed structure made up of carbon, nitrogen, and hydrogen

what are the nitrogenous bases for DNA?

adenine, cytosine, guanine, and thymine

what are the nitrogenous bases for RNA?

adenine, guanine, cytosine, and uracil

are lipids polymers?

no

triglycerides

fats and oils, a type of lipid, used for energy storage and insulation

phospholipids

type of lipid, structural foundation of cell membranes

steroids

play a role in membrane fluidity and signaling, examples are cholesterol, estrogen, and testosterone

what makes up a triglyceride

three fatty acid molecules and one glycerol

saturated fat

only single bonds, all carbon bonding slots are taken up by hydrogen

unsaturated fats

contain double or triple bonds

what kind of molecules can freely cross the semi permeable membrane?

nonpolar, small molecules

what kind of molecules require a transport protein to cross the semi permeable membrane?

polar molecules and ions (charged)

do prokaryotes have membrane bound nucleus?

no

archaea

prokaryotic organisms, often thrive in extreme environments, share similarities with eukaryotes

bacteria

prokaryotic organisms, diverse metabolic capabilities, play crucial role in ecosystems and human health

eukarya

organisms possessing a nucleus (plants, animals, fungi, protists)

what are the main differences in archaea from bacteria?

archaea lack petidoglycan int heir cell walls, their process of reading genetic material differs, and they have unique lipids in their membranes

coccus

spherical shaped bacteria

bacillus

rod shaped bacteria

spirillum

spiraled or helical shaped bacteria

gram positive bacteria

cells walls have a lot of peptidoglycan, thicker but less complex

gram negative bacteria

cell walls have less peptidoglycan, but are more complex structurally and have an outer layer of lipopolysaccharides

what color do gram positive bacteria stain?

purple

what color do gram negative bacteria stain?

pink

what are the 3 reasons that prokaryotes can reproduce so rapidly?

compact genome, simple cellular structure, and binary fission

where is DNA concentrated in prokaryotes

in the nucleoid

what are plasmids

small circular rings of extrachromosomal tissue, can be encoded with special traits

what is horizontal gene transfer?

the transfer of genetic material between individuals, not from parent to offspring

transformation

acquiring genes from surroundings, often from dead bacterial cells

conjugation

one way transfer between two live organisms

what plasmid is needed for conjugation?

F factor plasmids: one organism that is F+ can transfer the F+ plasmid to an F- organism, and once they have the F+ plasmid they can perform conjugation themselves

tranduction

viruses (phages) facilitate gene transfer by infecting bacterial cells

what does the prefix chemo mean?

the organism gets its energy from a high energy molecule (glucose)

what does the prefix photo mean?

the organism gets its energy from light

what does auto mean?

the organism gets its carbon from inorganic/non-biological cources

what does hetero mean?

the organism gets its carbon from organic/biological sources

mutualism

both species benefit from the relationship

parasitism

one species benefits at the cost of the other species

commensalism

either both species are unaffected or one benefits while the other is unaffected

obligate anaerobe

does not need oxygen, may be poisoned by it in some cases

obligate aerobe

require oxygen

facultative anaerobe

change their oxygen requirement depending on the environment