Answer:
A
Explanation:
Bc it is the highest point in choices
a. What is a star's spectrum?
A star's spectrum refers to the <em>"amount of light"</em> that stars they give off according to varying wavelengths. Since we cannot tell the amount of light a star gives off quantitatively from Earth, we can differentiate them according to how bright they appear.
b. Which spectrum is most common in stars?
Stars are classified according to their spectra <em>(elements in the star)</em>. They are classified into 7 types <em>(O, B, A, F, G, K and O). </em>The most common type is M, however, it gives off a dim light.
c. How can it differ from start to star?
Although stars follow a continuous spectrum, the spectra of a star differs from each other because <u>they do not give off the same amount of energy at the different wavelengths. </u>
d. What does the spectrum tell us about the star?
The spectrum can tell the<em> surface temperature</em> of the star. This means that a blue star (we often see it as a white-colored star from Earth) is hotter than that of a yellow star. A red star is considered the coolest star among all.
The spectrum of stars also allows the astronomers to study composition of the stars according to their <em>wavelengths.</em>
Answer:
Stem cell is taken either from bone marrow or from the blood directly
Explanation:
Stem cells are derived from two locations primarily a) Bone Marrow and b) Blood
The first step in this process is to remove the stem cell from its parent location and it is done in the following ways –
A) For deriving stem cell from blood – A drug with growth factor s is injected. Here no anesthesia is given to the patient. The growth factors leads to the movement of stem cells from bone marrow into the bloods. Blood with stem cells is taken out from the veins and filtered through the apheresis machine.
B) From Bone marrow – Bone marrow is removed from the pelvic bone through a needle and prepared for transplantation.
