Answer:
share a common ancestor
Explanation:
<em>The similarity in their embryos and embryonic development suggests that reptiles, birds, and mammals share the same ancestor.</em>
Similarity in the structure and development of embryo is one of the evidences that is been used by scientists to support the theory of evolution of species. According to the theory of organic evolution, all organisms are on earth as a result of descent with modifications from common ancestors.
<u>Reptiles, birds, and mammals are all vertebrates. They share some basic characteristics and are thought to have shared a common ancestor before each group took different adaptive channels leading to their differences as they currently exist.</u>
A is your answer. it cant be B because H doesn't equal 2 on both sides.it cant be C because S doesn't equal 3 on both sides of the equation . It also cant be D because Au doesn't equal 3 on the first part of the equation so your best answer is A. Hope this helps!!!!
B) is the correct answer. The flu virus does not have the same genetic makeup each year as with each individual it infects its rapidly mutating.
<span>Ian Waterman was able to sense pain and temperature because his
spinothalamic pathway was intact, but could not feel touch and limb position because of damage to his
lemniscus pathway. </span>
The lateral spinothalamic tract is a sensory pathway which carries sensory information like pain and temperature to the brain, across the thalamus. Free nerve endings which are located in the peripheral tissues are sensitive to cell damage. Those are primary neurons and they pass the sensory signal. Primary neurons synapse with secondary which are located in the spinal cord (white matter). These secondary neurons will ascend through the brainstem, medulla oblongata, pons and midbrain, until synapsing in the ventroposteriorlateral (VPL) nucleus of the thalamus. From the thalamus, the information is sent to cortex (somatosensory cortex).
Posterior column-medial lemniscus pathway is ascending spinal tract, carrying sensory information to the brain (sensory pathway). It conducts localized sensations of fine touch, vibration and proprioception (position sense) from the skin and extremities (muscles) to the central nervous system (cerebral cortex).
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.
