When you are exposed to bright light, a reflex is initiated and the muscles of your iris contract to decrease your pupil size.  The iris muscles are acting as a(n)

A. control center.
B. effector.
C. receptor.
D. positive feedback.


Answer: B

Anatomy & Physiology

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Match each term with its definition or description.

a. 1 b. 2 c. 3 d. 4 e. 5 f. 6 g. 7 h. 8 i. 9 j. 10 1. _____ Laryngopharynx 2. _____ Primary bronchi 3. _____ Nasal cavities 4. _____ Larynx 5. _____ Nasopharynx 6. _____ Secondary bronchi 7. _____ Alveoli 8. _____ Oropharynx 9. _____ Trachea 10. _____ Bronchioles

Anatomy & Physiology

Factors that are necessary for proper bone formation include all of the following, except

A) vitamin A. B) vitamin E. C) vitamin C. D) the hormone thyroxine. E) vitamin D.

Anatomy & Physiology

The FVRCP should begin at _____ to _____ weeks of age

Fill in the blank(s) with correct word

Anatomy & Physiology

The growth spurt seen in puberty is triggered by

A. calcitonin. B. growth hormone. C. sex hormones. D. parathyroid hormone. E. thyroid hormone.

Anatomy & Physiology