Research indicates that it is most commonly the ________ that contributes the extra chromosome to the zygote in cases of trisomy 21.
A. sperm
B. ovum
Answer: B
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Fever is caused by neurotransmitters released by pathogens.
Answer the following statement true (T) or false (F)
Answer the following statements true (T) or false (F)
1. The external auditory canal connects the throat to the middle ear and can allow the spread of infection from the throat to the middle ear. 2. The inner ear is responsible for the sense of hearing and equilibrium. 3. The bony labyrinth is divided into three parts: the cochlea, the vestibule, and the semicircular canals. 4. The membranous labyrinth is filled with endolymph. 5. The crista ampullaris is stimulated when you move your head.
If the sodium pump in the membranes of the photoreceptors were completely blocked, the result would be
A) grey images as only rods would function. B) darkness (blindness). C) an increase in visual acuity. D) the cells would not be able to produce glutamate. E) bright white light as all cones would be activated.
The insertion of a muscle
a. is only associated with smooth muscle b. contains muscle spindles c. is the movable end of attachment. d. source of development in the fetus. e. serves the same function as the origin