Answer:
Examples of mechanical weathering include frost and salt wedging, unloading and exfoliation, water and wind abrasion, impacts and collisions, and biological actions. All of these processes break rocks into smaller pieces without changing the physical composition of the rock.
Explanation:
Mechanical weathering involves mechanical processes that break up a rock: for example, ice freezing and expanding in cracks in the rock; tree roots growing in similar cracks; expansion and contraction of rock in areas with high daytime and low nighttime temperatures; cracking of rocks in forest fires, and so forth.
Answer:
<h2>C. placing carrier proteins in the membrane.</h2>
Explanation:
If there is no barrier preventing molecules from moving molecules, then there will be large movement of molecules from an area of high concentration to an area of low concentration. This passive process is known as diffusion. The phospholipid bilayer of a cell's membrane works as a barrier to large molecules, ions, and most hydrophilic molecules. Whereas small hydrophobic molecules can pass freely through the phospholipid bilayer, other molecules and ions are transported across the cell membrane with the help of transport proteins. Some transport proteins, allowing hydrophilic molecules and ions to passively move through them and across the cell membrane.
Examples: carrier proteins and channel proteins.
Placing carrier proteins in the cell membrane will allow the molecule to reach equal concentrations on the both the sides of the membrane and maintain that way over long time. In contrast, transport proteins known as pumps will use cellular energy, usually in the form of ATP, to transport molecules.
Placing equal numbers of intracellularly directed and extracellularly directed pumps would also equalize the concentrations of a molecule long over time. Pumps are to transport molecules against their concentration gradient, such as the sodium-potassium pump continuously moves sodium ions out of a cell.
Through the use of carrier proteins, there is equalization of concentrations of a hydrophilic molecule. This equalize the numbers of molecules on the inside and outside of the cell, but the pumps would continue moving the molecule inward, eventually resulting in more molecules inside of the cell than out.
The Cheshire cat caused the Queen of hearts to fall over
Answer:
D. Cell signalling which is released by one type of cell and acts upon a different cell
Explanation:
According to this question, adrenal cells near the kidney releases an hormone called ADRENALINE, which causes the cells of the heart to beat faster. This is an example of CELL SIGNALLING because chemical signals released by adrenal glands causes/triggers a response in the heart cells.
The chemical signal released by the adrenal cells is the ADRENALINE HORMONE, which induces a response in cells that are different from the cells of release (adrenal cells).
Answer:
The correct answer is option d. "a and b".
Explanation:
Plenty of methods had been developed to estimate the body size of dinosaurs such as the gigantic Sauropods. One of the first estimations that paleontologists used was the Archimedes principle, consisting in dunking the entire skeleton of a Sauropod into a pool of water and measure the water displacement or more precisely small dinosaur models. However this method requires the preservation of almost the entire skeleton. A more used and useful method is to measure the length of the legs from the hip to the foot and using a 2/3's power relationship convert that to a mass. This method is more used since it only requires a couple of leg bones, which are often well preserved.
