During fertilization, a sperm combines with a nucleus in the ovule to form
a. an egg. b. stored food. c. an ovary. d. a pollen grain.

advantage of using stem cells in medical research:

1.       it provides medical benefits in the fields of therapeutic cloning and regenerative medicine.

2. it provides great potential for discovering treatments and cures to a variety of diseases including parkinson disease, spinal cord injuries, diabetes, alzheimer’s disease and many more.

3. limbs and organ could be grown in lab from stem cells and then used in transplant or treat illness.

answer; both surfaces of the membrane are nonpermeable

. the sierra madre fault zone of southern california

. the san andreas fault california

the law of original horizontality explains:   why rocks appear in layers. correct answer: b the law suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed.   the principle is used by geologists to make assumptions about the relative ages of sedimentary rocks.