A ball of about eight cells formed about 50 to 60 hours after fertilization is called a(n) ________.
A. embryo
B. zygote
C. morula
D. blastocyst
Answer: C
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Oxygen debt in muscles may develop because of
A. the inability of myoglobin molecules to store enough oxygen when skeletal muscles are used strenuously for a minute or two. B. too much oxygen used in forming pyruvic acid when skeletal muscles are contracted strenuously for a minute or two. C. the inability of respiratory and circulatory systems to supply enough oxygen to skeletal muscles when used strenuously for a minute or two. D. too high a concentration of oxygen in the atmosphere.
The external ear ends at the ________.
A. auricle B. tympanic membrane C. external auditory canal D. tragus
The process of dissolving bone and returning its minerals to the bloodstream is known as ________
A) mineralization B) mineral deposition C) ossification D) crystallization E) resorption
When a female is pregnant, there is a lot of
A. FSH present in the blood. B. LH present in the blood. C. HCG present in the blood. D. All apply.