What do butterflies taste with?

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

Penicillin is hydrolyzed and thereby rendered inactive by penicillinase (also known as β-lactamase), an enzyme present in some resistant bacteria. the mass of this enzyme in staphylococcus aureus is 29.6 kd. the amount of penicillin hydrolyzed in 1 minute in a 10-ml solution containing 10-9 g of purified penicillinase was measured as a function of the concentration of penicillin. assume that the concentration of penicillin does not change appreciably during the assay. penicillin(μm) amount hydrolyzed(nmol) 1 0.11 3 0.25 5 0.34 10 0.45 30 0.58 50 0.61 (a) plot v0 versus [s] and 1/v0 versus 1/[s] for these data. does penicillinase appear to obey michaelis-menten kinetics? if so, what is the value of km? (b) what is the value of vmax? (c) what is the turnover number of penicillinase under these experimental conditions? assume one active site per enzyme molecule.

Question 1 which of the following allows cells to take in fluids? a. phagocytosis b. pinocytosis c. exocytosis d. receptor-mediated endocytosis question 2 molecules move along their concentration gradient (from areas of high concentration to low concentration) using active transport mechanisms. a. true b. false question 3 which of the following powers active transport (ie. provides the energy for)? a. glucose b. transport proteins c. atp d. phospholipids question 4 what type of lipid is a major component of the plasma membrane? a. cholesterol b. phosopholipids c. proteins d. triglycerides