Answer:
G 0 is a resting phase where the cell has left the cycle and has stopped dividing. The cell cycle starts with this phase.
Most of the marine animals have a stream lined body, which means, they have a sharp and pointed at the front. The pointed front of the organism allow to cut the resistance of the water. In case, the body is not pointed at the front and it is blunt, the water current and flow would resist the movement of the organism further. So, for the locomotion purpose, it is important to have a streamlined body. Further smooth and hair less body also decrease the resistance during the movement in the water.
When water freezes(ice) it expands slightly
think ice cube tray, and why the amount of ice you get is more than the amount of water you put in<span />
Fuel cells can make an electricity from a simple electrochemical
reaction in which oxygen and hydrogen combine to form water. There are several
different types of fuel cell but they are all based around a central design
which consists of two electrodes, a negative anode and a positive cathode.
These are separated by a solid or liquid electrolyte that carries electrically
charged particles between the two electrodes. A catalyst, such as platinum, is
often used to speed up the reactions at the electrodes. Fuel cells are
classified according to the nature of the electrolyte. Every type needs
particular materials and fuels and is suitable for any applications. The
article below uses the proton exchange membrane fuel cell to illustrate the
science and technology behind the fuel cell concept but the characteristics and
applications of the other main designs are also discussed. Proton Exchange Membrane Fuel Cells (PEMFC)
The hydrogen ions permeate across the electrolyte to the
cathode, while the electrons flow through an external circuit and provide
power. Oxygen, in the form of air, is supplied to the cathode and this combines
with the electrons and the hydrogen ions to produce water. These reactions at
the electrodes are as follows:
Anode: 2H24H+ + 4e-
Cathode: O2 + 4H+ + 4e- 2H2O
Overall: 2H2 + O22H2O + energy
PEM cells operate at a temperature of around 80°C. At this
low temperature the electrochemical reactions would normally occur very slowly
so they are catalysed by a thin layer of platinum on each electrode.
Answer:
Golgi receives a vesicle containing newly synthesized proteins that were sent by the endoplasmatic reticulum. Then it modifies the proteins and sends them where they need to go.
Explanation:
Protein synthesis is initiated in the cytoplasm when mRNA meets a free ribosome, which is the primary structure for protein synthesis. They read the mRNA code and add the correct amino acid using transference RNA to build the protein. The synthesizing protein is driven to the rough endoplasmic reticulum and translocated to the lumen. Once there, the protein suffers a few modifications, one of them is folding to become functional. Once membrane proteins are folded in the interior of the endoplasmic reticulum, they are <u>packaged into vesicles</u> and <u>sent to the Golgi complex</u>, where it occurs the <em>final association of carbohydrates with proteins</em>. The Golgi complex <u>sends proteins to their different destinies</u>. Proteins destined to a certain place are packaged all together in the same vesicle and sent to the target organ. In the case of membrane proteins, they are packaged in vesicles and sent to the cell membrane where they get incrusted.
