What produces the "lub dub" heart sounds?
A) the sound of blood traveling through the heart
B) the contraction of the atria, and then the ventricles
C) the relaxation of the atria, and then the ventricles
D) the vibrations of the ventricular and blood vessel walls when valves shut
Answer: D
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Answer the following statements true (T) or false (F)
1. The baby’s first breath is stimulated primarily by the lack of oxygen in the blood. 2. The baby’s first breath is stimulated primarily by an increase of carbon dioxide in the blood. 3. When a baby is born, it has only one spinal curve, adults have two. 4. Childhood extends from infancy to sexual maturity. 5. Both the deciduous teeth and the permanent teeth develop during childhood, deciduous at the beginning of childhood and the permanent teeth at the end.
Growth hormone exerts its effects on growth by
a. stimulating production of insulin-like growth factors b. directly invoking gene activity c. elevating blood glucose levels d. increasing fat metabolism e. increasing thyroid hormone levels
Explain how cations and anions form
What will be an ideal response?
When they secrete hormones, the ovaries and testes are considered what type of glands?v
a) endocrine b) exocrine c) apocrine d) sebaceous