Why do some people think that early mammals (including most Mesozoic forms) lacked a pinna (external ear)?
What will be an ideal response?
A pinna is lacking in monotremes, which have a cochlea with only half a turn. Only therians have a cochlea with two and a half turns, which allows better pitch discrimination. A pinna provides more acute directional hearing, and it is possible that it did not evolve until the sense of hearing was acute (as revealed by the coiling of the cochlea).
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Select the correct statement regarding tissue repair.
A) Granulation tissue is highly susceptible to infection. B) Inflammation causes capillaries to dilate and become permeable. C) Granulation tissue is another name for a blood clot. D) The clot is formed from dried blood and transposed collagen fibers.
Match the enzyme with the products of its digestive activity.A. Glucose and galactoseB. Amino acidsC. Fatty acids and glycerolD. Maltose and isomaltoseE. Polysaccharides and disaccharidesCarboxypeptidase
Fill in the blank(s) with the appropriate word(s).
Where does myeloid hemopoiesis take place in adults?
A. Yellow bone marrow B. Thymus C. Spleen D. Liver E. Red bone marrow
Which of the following structures is NOT found on the femur?
A. Lesser trochanter B. Linea aspera C. Obturator foramen D. Gluteal tuberosity E. Fovea capitis