final study guide (Ch.5-8) Flashcards
What are the different elements present in each macromolecule?
carb. COH, lipids COH, proteins COHN, nucleic acids COHNP
how do you tell carbohydrates apart from lipids?
carbohydrates have a more even distribution of C, H, and O, while lipids tend to have long chains of C, and H with very few O.
what is the function of carbohydrates?
energy and structure as well as long term storage.
what are monosaccharides classified by?
location of carbonyl group and # of carbons
what covalent bond links monomers of carbohydrates?
glycosidic linkages
What is starch and glycogen?
starch is the storage sugars of plants and glycogen is the storage sugars of animals.
why can’t humans digest cellulose?
it is much heavier than water and has strong hydrogen bonds. also our enzymes can’t hydrolyze beta linkages.
what is glycerol?
3-carbon alcohol w/ hydroxyl group (OH) attached to each carbon.
what is the bond that holds glycerol and fatty acids together?
ester linkage (through dehydration reaction)
what makes up amino acids?
a central carbon (alpha) attached to amino group (NH2), carboxyl group (C=0, OH), R group, and a H.
what are the bonds that connect amino acids?
peptide bonds
What is the primary, secondary, tertiary, and quaternary structure of proteins?
primary is unique sequence of amino acids, secondary is the hydrogen bonds that cause coils and folds, tertiary is determined by r group, and quaternary is when 2 polypeptide chains form a macromolecule.
what are nucleotides made up of?
phosphate group, sugar, and a nitrogenous base.
what replaces thymine in RNA?
uracil
where does protein synthesis occur?
in ribosomes
what is a nucleoside?
nitrogenous base and sugar
what are the 2 nitrogenous bases and what do they do?
pyrimidines( single 6-membered ring) and purines (1 six-membered ring attached to a 5-membered ring)
what is the bond that holds nucleotides together?
phosphodiester bonds
What do plant cells have that animal cells do not have?
Plant cells have a large vacuole in the middle to store water and also contain chloroplasts as well as a cell wall and a plasmodesmata.
what’s the difference between bound and free ribosomes?
bound ribosomes are attached to the ER or nuclear envelope whereas free ribosomes are in the cytosol
What is part of the endomembrane system?
Nuclear envelope, ER, Golgi apparatus, lysosomes, vacuoles, and the plasma membrane.
what does the smooth ER do?
it synthesizes lipids, metabolizes carbs, stores calcium, and detoxifies poison
What is the nucleolus?
it’s in the center of the nucleus and produces ribosomes and rRNA
What is the function of the Golgi apparatus?
modifies the products of the ER, manufactures certain macromolecules, and sorts and packages materials into transport vesicles.
What does the Golgi apparatus consist of?
flattened membranous sacs called cisternae
What is the structure/function of lysosomes?
made up of hydrolytic enzymes that hydrolyze proteins, fats, polysaccharides, and nucleic acids. They also recycle organelles through a process called autophagy.
What are peroxisomes?
metabolic compartments that contain the enzyme catalase to convert hydrogen peroxide into water.
explain the structure of chloroplasts
granum are stacks of thylakoids and within the thylakoid membranes are photosystems in which photosynthesis takes place. The stroma is the liquid that surrounds that granum.
What are the 3 molecular structures inside of the cytoskeleton and describe their roles?
microtubules are the thickest and maintain cell shape and motility. microfilaments are the thinnest and are used in muscle contraction and cell division. intermediate filaments are in the middle and anchor the nucleus.
What is dynein and how does it work?
they are motor proteins in which their arms alternately grab, move, and release the outer microtubules.
what are the three layers of a plant’s cell walls?
the primary cell wall is thin and flexible. The middle lamella is a thin layer in between the primary walls of adjacent cells. Secondary cell walls are in some plants and are in between the plasma membrane and the primary cell wall.
what are plasmodesmata?
channels in between adjacent plant cells.
what turns plasma membranes solid?
low temperatures and more saturated fatty acids.
how do membranes stay fluid during cold temperatures?
by adding cholesterol. (cholesterol restrains movement in hot temps and encourages movement in cold temps)
What’s the difference between peripheral and integral proteins?
peripheral proteins are not embedded in the membrane and integral proteins penetrate the membrane
What’s a glycoprotein?
when a carbohydrate binds to a lipid on the plasma membrane.
What does not cross the membrane easily and what helps them cross?
polar molecules, large molecules and channel proteins help them cross
What helps the passage of water across a membrane and what is the movement of water across a membrane called?
aquaporins (protein complex) and osmosis (process)
solute vs solvent?
solute is the substance that gets dissolved and a solvent is the substance that dissolves another substance.
hypotonic vs hypertonic solution?
hypotonic is when there is more solution inside the cell and the outside has less solution so the water moves into the cell. hypertonic is when there is more solution on the outside of cell, so water moves out of the cell.
What is an electrogenic pump?
a transport protein that generates a voltage across a membrane. (a common type is a H+ pump)
What is a catabolic and an anabolic reaction?
catabolic releases energy by breaking things down and anabolic absorbs energy by building molecules
What does the first law of thermodynamics state?
the energy of the universe is constant and is able to be transformed or transferred, but not created or destroyed.
What does the second law of thermodynamics state?
during every energy transfer, some energy is lost and decreases the entropy of the universe.
What is entropy (∆S) and how does an increase in temp, enthalpy, and free energy affect it?
entropy is disorder. Increased temp causes increased entropy. Increased enthalpy causes decreased entropy. Increased free energy causes entropy to decrease.
What is enthalpy?
The amount of energy released or absorbed in a chemical reaction. So if ∆H is positive, it absorbs energy and if its negative it releases energy.
How does ∆G (free energy) affect spontaneity? what is free energy?
if ∆G is positive, it is nonspontaneous. If ∆G is negative, it is spontaneous. the measure of a system’s instability and tendency to change to a more stable state.
Where does the release of energy come from in ATP?
the chemical change to a state of lower free energy
What is a hydrolysis and dehydration reaction?
hydrolysis breaks molecules down by adding water. Dehydration combines molecules by releasing a water molecule.
What are cofactors and coenzymes?
cofactors are nonprotein enzyme helpers and coenzymes are organic cofactors.
What is allosteric regulation?
The process in which a regulatory molecule binds to another part of an enzyme which can either make it more or less functional
