Which type of junction forms an impermeable barrier between epithelial cells?

Which type of bird is most likely to benefit from air sacs which reduce its weight?

A) birds, such as geese, which migrate great distances B) birds that chip away wood, such as woodpeckers C) diving birds D) birds that rip apart prey, such as hawks and eagles

Multiple mechanisms for small RNA (sRNA)-mediated translational regulation exist but all are unified by inactivating protein synthesis of the target mRNA

Indicate whether the statement is true or false.

Daphnia will switch from parthenogenesis to sexual reproduction under all of the following conditions except:

A. warm temperatures. B. decreased food supply. C. cool temperatures. D. accumulation of wastes. E. None of the answer options would cause Daphnia to switch.

Ever since the antibiotic drug penicillin was discovered in 1928, the incidence of resistant bacteria has steadily increased as a direct result of

(a). biodiversity. (b). natural selection. (c). homeostasis. (d). development. (e). reproduction.