What best summarizes the oocyte's contribution to the zygote?
a. The oocyte contributes paternal DNA
b. Numerous substances are contributed by the oocyte, including maternal DNA, enzymes, yolk, and proteins.
c. Nothing; an oocyte forms after several cleavages of the zygote.
d. Oocytes are the source of the enzymes used by the sperm to penetrate the egg's membrane.
b
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Refer to the paragraph about Kawakubo's group. Kawakubo's group created a glycoprotein with a terminal NAG (i.e., a protein with NAG attached to its end). Their hypothesis is that the terminal NAG, and not the protein component , is responsible for the damage to the cell wall in H. pylori. What would be the most appropriate control for testing this hypothesis?
A) Grow H. pylori in a test tube (in vitro) with no glycoprotein. B) Destroy the H. pylori by exposing them to a hypotonic solution. Then add the glycoprotein and observe. C) Expose other species of bacteria to the glycoprotein. D) Grow H. pylori in a test tube with a glycoprotein that has its terminal NAG removed.
The hormone that influences sodium reabsorption in the kidney is:
a. antidiuretic hormone b. cortisone c. aldosterone d. corticotropic hormone e. adrenalin
If someone who is severely allergic to bee stings gets stung, the person may experience anaphylactic shock, which can cause a fatal drop in blood pressure
The drop in blood pressure is due to an inappropriate release of histamine in response to the sting. Histamine causes massive vasodilation, so how does this affect blood pressure?
The respiratory systems of fishes, frogs, sponges, and earthworms are similar in that they
A) exchange gases across a moist respiratory surface. B) have internal respiratory structures. C) utilize a complex network of air-conducting tubes. D) employ an extensive system of air sacs that ensures a unidirectional flow of air. E) have a countercurrent exchange system.