Question

question 23 (1 point) ✓ saved
complement is found in the
red blood cells.
white blood cells.
platelets.
plasma.
question 24 (1 point) ✓ saved
samples collected early in an infection are called __________, while samples
collected later from the same subject are called __________.
confirming, diagnostic
primary, secondary
acute, convalescent
titer, serological
question 25 (1 point) ✓ saved
the majority of white blood cells in circulation include
neutrophils and lymphocytes.
eosinophils and basophils.
macrophages.
erythrocytes.

Explanation:

• Question 23: Complement is a part of the immune system. It consists of a series of proteins. These proteins are found in the plasma (the liquid part of blood). Red blood cells carry oxygen, white blood cells are involved in immune responses (but complement is not stored within them as a main location), and platelets are involved in blood - clotting.
• Question 24: In serological testing (related to the study of blood serum and immune responses), samples taken early in an infection (when the infection is active) are called acute - phase samples. Samples taken later (when the patient is recovering) are called convalescent - phase samples. “Confirming” and “diagnostic” are more general terms not specific to the timing of sample collection in this context. “Primary” and “secondary” are terms more related to immune responses (like primary and secondary immune responses) rather than sample collection times. “Titer” is a measure of antibody concentration and “serological” is a general term for the study of serum.
• Question 25: Neutrophils are the most abundant white blood cells (accounting for about 40 - 75% of all white blood cells in circulation), and lymphocytes (T - cells, B - cells, and natural killer cells) are also very common (about 20 - 50% of white blood cells in circulation). Eosinophils and basophils are less abundant (eosinophils 1 - 6%, basophils <1%). Macrophages are a type of phagocyte but are not the majority in circulation (they can be found in tissues). Erythrocytes are red blood cells, not white blood cells.

Answer:

• Question 23: plasma
• Question 24: acute, convalescent
• Question 25: neutrophils and lymphocytes