Which of the following statements regarding intrinsic regulation of the heart is true?
A. If cardiac muscle cells are slightly stretched, they have a stronger contraction force.
B. The heart's pumping effectiveness is greatly influenced by small changes in afterload.
C. Stretching the SA node will decrease generation of action potentials in the node.
D. If cardiac muscle cells are slightly stretched, they have a weaker contraction force.
E. Decreased venous return increases cardiac output.
Answer: A
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Which type of exocrine gland accumulates its secretory product in the cytosol of its cells until the cell ruptures and becomes part of the secretory product?
a) Apocrine b) Exocrine c) Holocrine d) All of these answer choices are correct. e) None of these answer choices are correct.
Which of the following is the function of the combination of epidermal ridges and dermal papillae?
A) increase storage of nutrients in the digestive tract B) increase surface area for diffusion between the dermis and epidermis C) increase sensory reception D) increase secretion of milk in specialized integumentary glands E) increase large reserves of lipids in adipose tissue
__________ fluid prevents friction between the heart and the pericardium when the heart beats
Fill in the blank(s) with correct word
Which of the following is FALSE regarding single-unit smooth muscle cells?
A. They have an individual neuron innervating of each individual smooth-muscle cell. B. They have many gap junctions between cells. C. They may have pacemaker activity. D. They may respond to stretch by contracting. E. They exhibit tone.