Unicellular organism ...................................................................................................
The spindle fibres of a chromosome failed to separate a chromosome to sister chromatids during anaphase of mitosis resulting in an additional sister chromatid being pulled into a Daughter cell, hence having 39 chromosomes; and the other Daughter cell having one less chromosome.
<u>Answer:</u>
Enzymes 'reduces the activation energy' of both Exergonic and Endergonic Reaction by acting as a catalyst.
<u>Explanation:</u>
- For example, in the case of 'carbonic anhydrase', enzymes act rapidly causing the chemicals to 'react 107 times faster' than they would normally.
- Enzymes are substrate specific meaning an enzyme working on one substance may not work on another.
- Function of the enzyme is identified by its 'shape of the protein' and arrangement of these molecules produces an area called activation site.
I would say all of the above. A mix of all those styles works best
The right answer is The pressure in veins is lower than in arteries, causing less seepage of blood.
The arteries are the vessels located at the exit of the heart towards the organs. When the heart contracts like a pump to expel the blood to the arteries, the pressure is very strong. This is called systolic pressure. To cope with this pressure, the arteries have a thick and elastic wall, to be able to stretch without breaking. The arteries have an average diameter of 2.5 centimeters, against less than 2 mm for arterioles.
Unlike the arteries, the veins are subjected to a weak pressure, since the blood starts from the organs and not from the heart. The walls of the veins are therefore thin and fairly rigid because they have little resistance to provide against the pressure. The diameter of the veins and venules is rather small (smaller than arteries) and hardly varies. Veins and venules contain about 75% of the blood. During a cut, the blood of the veins gradually trickles.
So from these explanations, we can conclude that the propositions B; C and D are false, it is rather their opposite that is right.