The difference between normal and sickle-cell hemoglobin is _____
a. the number of amino acids in the molecule
b. the substitution of one amino acid for another
c. the number and orientation of the amino acid chains attached to the heme portion of the molecule
d. the number of oxygen molecules that can be carried
e. the types of blood cells that produce each protein
ANSWER: b
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This type of tissue provides the primary support and strength in the shoot system
a. dermal tissue b. epidermal tissue c. cortical tissue d. parenchyma e. vascular tissue
Your friend wants to know why patients that receive organ transplants have to take immune-suppressing drugs for the rest of their lives. You tell her that:
1.The transplanted organ will only work properly with the immune-suppressing drugs. 2.The MHC markers of the donor organ do not match the patient, so the patient’s immune system will reject the organ without the medication. 3.The donor organ has a different MHC marker, which will attack and kill the patient’s cells if the medication isn’t taken regularly. 4.The medication is needed so the patient will not get sick after the transplant, which could cause the new organ to not function properly.
Fungi are major pathogens for
A. Animals. B. Bacteria. C. Insects. D. Plants.
What is the effect of increased levels of parathyroid hormone?
A) Increased blood calcium levels B) Decreased blood calcium levels C) Increased estrogen levels D) Decreased metabolism E) Increased metabolism