The Sidereal Day is 4 minutes shorter than the Mean Solar Day, because the rotation of the Earth on its axis, and the orbiting of the Earth around the Sun, are both counterclockwise, as viewed from above (or north of) the Ecliptic Plane. See planetary retrograde motion for an example of the opposite situation.
The reason that the Solar Day varies around the Mean Solar Day is that the Earth moves at different speeds through its orbit around the Sun. This is in keeping with Kepler's Second Law of Planetary Motion.
Please note that the Mean Solar Day changes over a long period of time, due to the slowing of the rotation of the Earth due to tidal forces exerted on the Earth primarily by the Moon. For example, the Mean Solar Day was about 23 hours about 250 million years ago.
A cell has cytoplasm, a cell wall, naked DNA and ribosomes. Based on this information, this could be <span>A. A cell from a pine tree.</span>
Answer:
The two main DNA lesions formed by exposure to UVB are cyclobutane pyrimidine dimers (CPD) and 6-4 pyrimidine pyrimidone photoproducts (6-4PPs), and its Dewar isomers.
Answer:
(2) exchange food, oxygen, and waste between
mother and fetus
Explanation:
In most mammals like humans, the fetus produced as a result of the fertilization of the sperm and egg, develops in the uterus or womb of the female. However, this developing fetus cannot yet fend for what it requires for survival and is still dependent on the mother e.g nutrients, oxygen etc. How do this substances get to the fetus? Here comes the role of the PLACENTA.
Placenta is an organ in the uterus that serves as a connection between the mother and the fetus in her womb. The placenta enables the mother to pass digested nutrients to the fetus and exchange gases (oxygen and Carbondioxide) between them via the umbilical cord. The placenta also enables the mother remove waste produced by the fetus into her bloodstream.
Antarctica would be the answer
