You would expect an earthworm to have no exoskeleton because as you see it is very flexible and soft. Organisms with such have body parts that are divided and an earthworm do not have any visible parts on them also having an exoskeleton would not allow an organism to move like an earthworm does.
Explanation:
In the majority of cases, the extra copy of chromosome 21 comes from the mother in the egg.
In a small percentage (less than 5%) of cases, the extra copy of chromosome 21 comes from the father through the sperm.
In the remaining cases, the error occurs after fertilization, as the embryo grows.
Answer:
C. Four Haploid Sperm Cells
Explanation:
Meiosis is a cell division measure that creates four haploid cells (gametes) from a solitary diploid germline cell. In males, meiosis is essential for spermatogenesis, the cycle to produce sperm. Sperm are the haploid cells that are produced in meiosis.
Meiosis is a profoundly moderated cell division measure in eukaryotes that produces 4 cells (gametes) from a solitary cell (mother). Nonetheless, Nondisjunction in the male of Drosophila causes much of the time sperm with an addition or loss of chromosomes.
Correct Completed Questions; Susan, a 67 year old female is experiencing ataxia, or poor muscle coordination. Doctors perform a neurological exam and they find that Susan is not positive for the Romberg test. Describe what these findings suggest about the sources of Susan's ataxia.
Answer:s
In order to test for balance and positioning(proprioception) as a measure of neurological function, or to test level of intoxication alcohol during driving, Romberg test is usually conducted,which can be negative or positive.It is generally used to investigate the cause of loss of motor control in individuals.
Explanation:
A positive result showed that her ataxia was due to loss of positioning due to loss of sensory from sensory neurons.However if negative as in the case of Susan, then it is to due to abnormality/dysfunctions in the cerebellum, and not due to loss of sensory functions,