The web page (below) provides: Mesozoic ("Middle Life") Era This is the second of three geologic eras squeezed into the Phanerozoic ("Evident Life") Eon that covers the last 10% of Earth's whole geologic history. This is the era we all think of when we imagine the Ancient Earth! Rampaging dinosaurs! Dive-bombing pterodactyls! Endless forests of giant ferns! Erupting Volcanoes! (Sorry, no cave men! They didn't show up until the end of the Cenozoic.)
The Mesozoic Era lasted about 180 million years, from about 245 million years ago to about 65 million years ago. The Mesozoic is divided into just three time periods: the Triassic, the Jurassic, and the Cretaceous. Since lots of things were going on in each time period, we can only summarize the events. You can learn more by going to your library or searching the Internet for words like "Mesozoic" or the names of each of the periods.
In the view above, we see Earth in the middle of the Jurassic Period, in mid-Mesozoic times (sort of a middle-middle view). The supercontinents Gondwanaland and Laurasia collided some time back to form a single super-super continent called Pangea ("All-Earth"). But plate tectonics continues its irresistible motions, and even as we look, Pangea is beginning to break up into the continents we know now. At upper left, North America is just breaking away from the northwest coast of Africa, and the Atlantic Ocean and Gulf of Mexico are beginning to form. The Appalachian Mountains of the eastern United States are a high, rugged mountain range, something like the Rocky Mountains of today. Over the next fifty million years or so, South America, India, and Antarctica will all break away from Africa and move toward their present positions.
Life is diversifying rapidly, and beginning to look familiar. The dominant animals on both land and sea are reptiles, the most famous of which are the dinosaurs. Dinosaurs began in the Triassic, spread during the Jurassic, and dominated Earth in the Cretaceous. They are so prominent that the Mesozoic is also called "The Age of Reptiles." But dinosaurs are not the only life form around: birds and mammals also appear during the Mesozoic, as well as deciduous trees and flowering plants.
The climate during the Mesozoic is warm; so warm that there are no ice caps at all, even at the poles! Plants grow like crazy in the warmth and moisture, so there is food everywhere for your average hungry 50-ton Ultrasaurus! So what happened to this Dino Paradise? More change! A mass extinction like those in the Paleozoic ended the idyllic Mesozoic Era (if you can call dodging your friendly local T-Rex as idyllic). More than half of all existing life forms disappeared, including virtually all of the dinosaurs. Why? There are many hypotheses, including disease, volcanic eruptions, and giant impacts. (Pay a visit to the Dinosaur Floor to learn more.
seems based on text above, most correct is "A" definitely not "C"
Every one color match up to light of a certain wavelength produced by the atom when an electron marks a changeover among permissible orbitals. Each color signifies a jump of the electron with resultant emission of photons of certain energy conforming to the vertical colored stripes. The scientist can assess these energies by means of einstein equation for the energy of a photon which is E = h. v where v is the frequency of the emitted photon that can be assessed by means of the wavelength and h is a constant. Then it can recreate the jumps and accordingly figure out the orbitals and perhaps the map of the structure of the atom.
- Synaptic vesicles fuse to membrane of axon terminal.
- Acetylcholine is released into the synaptic cleft.
- Acetylcholine binds to its receptors on the junctional folds.
- Junctional folds become depolarized.
- Action potential is initiated on the sarcolemma.
Action potential travels through the membrane of the presynaptic cell causing the channels permeable to calcium ions to open. Ca2+ flow through the presynaptic membrane and increase the Ca concentration in the cell which will activate proteins attached to vesicles that contain a neurotransmitter (e.g. acetylcholine). Vesicles fuse with the membrane of the presynaptic cell, thereby release their contents into the synaptic cleft-space between the membranes of the pre- and postsynaptic cells. Neurotransmitter binds to its receptors on the postsynaptic membrane and its binding causes depolarization of the target cell (muscle cell).
<em>Mechanism, Evidence ... - TopprThe transportation occurs in the direction of the source to sink. Transport of organic solutes from one part of the plant to the other through phloem sieve .</em>