Is the heart always pumping blood when pressure in the left ventricle is rising? Explain
What will be an ideal response?
No. When pressure in the left ventricle first rises, the heart is contracting, but blood is not leaving the heart. During this initial phase of contraction, called the period of isovolumetric contraction, both the AV valves and the semilunar valves are closed. The increase in pressure is the result of the cardiac muscle contracting. When the pressure in the ventricle exceeds that in the aorta, the aortic semilunar valves are forced open, and blood is rapidly ejected from the ventricle.
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A young sheep 3-7 months of age is a _____________________________
Fill in the blank(s) with correct word
Which of the following might happen if a person begins laughing while swallowing a liquid?
A. Relaxation of the soft palate allows liquid to enter the nasal cavity. B. Laryngeal constriction forces liquid through the pharynx. C. Nothing; swallowing will be normal. D. The tongue might be swallowed. E. Peristalsis will not begin.
Which of the following is NOT a result of estrogen production?
A. Shedding of the uterine lining to start the menstrual cycle B. Increased long bone growth during puberty C. Maturation of oocytes within follicles D. Effects on fat deposition and other secondary sex characteristics
The specialized cells found in the capsule epithelium are called ________. These cells have long cytoplasmic extensions called ________.
Fill in the blank(s) with the appropriate word(s).