Describe the processes of vasodilation and vasoconstriction
What will be an ideal response?
Vasodilation occurs when precapillary sphincter muscles relax so a greater quantity of blood can travel through a particular capillary bed. During strenuous exercise, for example, vasodilation would allow more blood to travel through the capillaries supplying the muscles being vigorously exercised. Vasoconstriction occurs when precapillary sphincter muscles constrict to restrict blood from a particular capillary bed. When you are very cold, vasoconstriction prevents capillary flow to a certain degree to your appendages, to save heat. In this example, your hands and feet then feel cold.
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Which medium can be described as a nutritionally rich medium used to grow various microor-ganisms, either as a broth or as an agar, with or without added blood?
a. Chocolate b. Colistin, nalidixic acid (CNA) blood c. Brain-heart infusion (BHI) d. Thioglycollate broth
Monoclonal antibodies used in many commercial applications are derived from ____
a. mice b. viruses c. genetically modified bacteria d. human volunteers e. horses
DNA rearrangements in eukaryotes can
A) cause chromosome puffs. B) enhance production of the certain gene products. C) increase the diversity of possible gene products from a limited number of genes. D) allow for epigenetic regulation. E) enhance production of the certain gene products and increase the diversity of possible gene products from a limited number of genes.
Body mass index (BMI) is calculated from what factors?
A) muscle density and weight B) age, weight and height C) fat density and age D) weight and height