Describe how the iris regulates light entry into the eye during sympathetic and parasympathetic stimulation
What will be an ideal response?
The iris contains two muscles that improve vision by regulating how much light passes through the pupil. The pupillary sphincter muscle contracts following parasympathetic stimulation and constricts the pupil to reduce the amount of light entering the eye. The pupillary dilator muscle is arranged in a radial pattern and contracts following sympathetic stimulation. It enlarges the pupil to permit more light to enter the eye.
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Match the following:
A) Anaphase B) Late prophase C) Telophase D) Metaphase E) Early prophase 1) Chromosomes decoil to form chromatin. 2) Chromosomal centromeres split and chromosomes migrate to opposite ends of the cell. 3) Nuclear membrane and nucleolus disintegrate. 4) Chromosomes align on the spindle equator. 5) Centrioles move to opposite ends of the cell.
Assume a person has a blood pressure recording of 125/77
a. What is the systolic pressure?____________________ b. What is the diastolic pressure?____________________ c. What is the pulse pressure?____________________ d. What is the mean arterial pressure?____________________ e. Would any sound be heard when the pressure in an external cuff around the arm was 130 mm Hg? ____________________ f. Would any sound be heard when cuff pressure was 118 mm Hg? ____________________ g. Would any sound be heard when cuff pressure was 75 mm Hg? ____________________
Antibodies are
a. gamma globulins. b. a type of plasma protein. c. produced by B lymphocytes. d. two of these answers. e. all of these answers.
Which of the following statements regarding phagocytes and phagocytosis is true?
A. Macrophages, monocytes, and mast cells are phagocytes. B. Contact of phagocytes with microbes stimulates the phagocytes to release chemicals that mediate the inflammatory response. C. Phagocytosis is stimulated by the presence of proteins called rhodopsins. D. Phagocytosis is the process by which leukocytes exit the bloodstream. E. Phagocytosis is a process that only occurs within the bloodstream.