Question

question 7
an increased breathing rate is often associated with which of the following?
a increased heart rate to deliver oxygen through the cardiovascular system
b decrease in carbonic acid levels in the blood
c decreased ph in the blood
d increase in cellular respiration in the tissues
e decrease in oxygen levels in the blood

question 8
insects use ______ as their respiratory organs.
a internal gills
b body surface
c external gills
d tracheae
e lungs

Explanation:

Question 7: Increased breathing rate is triggered by low blood oxygen (hypoxia), which signals the body to inhale more oxygen. Other options (e.g., increased heart rate, CO₂ decrease) are not direct triggers for faster breathing.
Question 8: Insects use a network of tracheae—tiny tubes that deliver oxygen directly to cells—for respiration, unlike gills (aquatic organisms) or lungs (vertebrates).

Answer:

Question 7: E. decrease in oxygen levels in the blood
Question 8: D. tracheae