B-lymphocytes are categorized as part of the adaptive branch of the immune system for all of the following reason but one. which of the following is not one of the reasons b-lymphocytes are considered part of the adaptive immunity? a) their receptors will bind to only one antigen. b) they are a first line of defense that can begin killing pathogens immediately. c) they require costimulation from an activated t- cell. d) they produce memory cells when activated.

15 ! come and answer! a(n) is the general term for an infectious disease that has spread across a city, region, or country.

Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.

Select the correct answer. which mutation is harmful to the organism? a. a mutation allowing moths to camouflage better on blackened tree bark b. a mutation making staphylococcus aureus resistant to the antibiotic methicillin c. a mutation inhibiting human immunodeficiency virus from attaching to and entering the cell d. a mutation causing uncontrolled cell division e. a mutation giving plant leaves a bitter taste to discourage herbivores from eating them