The correct answer is "C".
Onion cell is a plant cell and human cheek cell is an animal cell. Hence, onion cell has a cell wall<span> but not in human cheek cells because animal cells do not have cell wall. Both cells have single nucleus. Since, human cheek cell is an animal cell, chloroplasts are cannot be seen in the human cheek cells.</span>
Answer:
D shrub clippings
Explanation:
this is because they don't decompose like the other choice and are not rich in nutrients
Answer:
The correct answer is B. Tapping the patellar tendon will usually result in a spinal reflex.
Explanation:
The patellar reflex is the involuntary contraction of the quadriceps femoris muscle by flexion of the patellar tendon. It is a reflex of spinal or stretching type. It was discovered, studied and first reported in 1875 by William Erb.
By striking the patellar tendon, the leg is extended as alpha motor neurons direct a nerve impulse to the quadriceps femoris muscle. The femoral nerve, responsible for such reflex, extends throughout the thigh and its synapses are found in the lumbar spinal nerve 2 to 4 of the spinal cord. Therefore, this movement is involuntary and responds to a need for automatic regulation of body muscles.
It is called IMPLANTATION. the zygote is embedded into the uterus lining. Starting from there, the zygote will soon develop into a embryo and soon a fetus under amniotic fluid and an umbilical cord to transfer food and waste in and out.