Certain substances can't pass through the membrane but need to get in/out. What can cells use to allow specific substances in/out, "doors"
A. Protein tunnels
B. Protein ions
C. Protein channels
D. Protein stations

please don’t give me the link to get the answer .. it doesn’t work

Dominant over the mutant vermilion (bright red) allele. a homozygous wild-type female fly is mated with a vermilion male fly. predict the eye colors of f1 and f2 generations. (assume that the f1 flies are allowed to interbreed to produce the f2 generation.)

Football players often sustain lateral blows to the extended knee. which of the ligaments is (are) damaged as a result? a. suprapatellar b. oblique popliteal and extracapsular ligament c. medial collateral, medial meniscus, and anterior cruciate d. arcuate popliteal and the posterior cruciate

Apuppy’s tendency to chew is inherited through which of the following? a. through learned behavior b. through genes c. through seasonal cycles d. through hibernation