Answer: A
Explanation:
Gravity is when you drop something, but in this case you aren’t dropping the ball. It definitely isn’t chemistry because you aren’t changing molecules or anything so that only leaves A which is the most reasonable answer anyways.
The Nucleus is sort of like the "brain" of a cell.
<h2>
Reproductive Method </h2>
Explanation:
<em>The rank in order from the most specific which is following .</em>
<em>(1) Reproductive isolating mechanism</em>
<em>(2) Sperm-egg incompatibility in sea urchins</em>
<em>(3) Gametic isolation </em>
<em>(4)Prezygotic isolating mechanism</em>
<em>(1) Reproductive isolating mechanism-</em> The components of regenerative confinement are an assortment of transformative instruments, practices and <em>physiological procedures basic for speciation.</em> They keep individuals from various species from delivering posterity, or guarantee that any posterity are sterile.
(<em>2) Sperm-egg contradiction in ocean urchins-</em> Bindin is a gamete acknowledgment protein known to control species-explicit <em>sperm-egg grip</em> and layer combination in ocean urchins.
<em>
(3)Gametic isolation - Prezygotic hindrances </em>keep preparation from occurring. Gametic disengagement is a sort of prezygotic hindrance where the<em> gametes (egg and sperm) </em>come into contact, yet no preparation happens. Gametes might be not able to remember each other in various species
<em>
(4) Prezygotic isolating mechanism- </em>while postzygotic segregation forestalls the arrangement of rich posterity. Prezygotic systems incorporate environment segregation, mating seasons, "mechanical" disconnection, gamete detachment and conduct seclusion.
Sternal angle marks the joint between the sternum and the 2nd rib.
Option E.
<h3><u>Explanation:</u></h3>
Sternum is the breast bone which is a dorsi ventrally flattened bone present in thorax of human. It gives the support for the ribs where the ribs join. A sternum has three parts - Manubrium sterni, body of sternum and the xyphoid process.
The sternum has attachments of a total of 10 ribs and clavicle. The clavicle and the first rib joins in the Manubrium sterni, and the 3rd to 10th rib joins in the body of sternum. The 2nd rib joins in a facet which is partly in Manubrium sterni and partly in body of sternum. This place id also called the sternal angle. So the sternal angle marks the joint of 2nd rib to sternum.