What does therapeutic cloning involve?
developing genetically identical cultures of human cells for use in drug testing developing genetically identical cultures of human cells for use in drug testing
b. infertile couples to conceive by injecting the father’s sperm into the mother’s egg
c. producing embryonic stem cells for medical use
d. replacing a mutant allele in an embryo to prevent genetic disease

Which of the following cell structures is significantly different between gram- positive and gram-negative bacteria?

18. determine whether each stateme blank space given. ach statement is true (t) or false (f). place your answer in the 8. when a cell is put into an isotonic solution, individual wat put into an isotonic solution, individual water molecules cannot move back and forth across the cell membrane. d. when a cell is put into a hypertonic solution, there is a net movement of water molecules across the cell membrane into the cell. c. when a cell is put into a hypotonic solution, there is a net movement of water molecules across the cell membrane out of the cell. d. the movement of any solvent across a semi-permeable membrane is called osmosis. e. carrier proteins have the ability to change shape and physically move molecules across the cell membrane. f. in facilitated diffusion, the concentration of the molecules to be moved across the cell membrane is higher inside the cell.

Which of the following observations darwin shape his concept of descent with modification? a) species diversity declines farther from the equator.b) fewer species live on islands than on the nearest continents.c) birds can be found on islands located farther from the mainland than the birdsê¹ maximum nonstop flightdistance.d) south american temperate plants are more similar to the tropical plants of south america than to thetemperate plants of europe.e) earthquakes reshape life by causing mass extinctions.