Answer:
The correct answer would be non-disjunction.
Down syndrome refers to the genetic disease caused by the non-disjunction of chromosome number 21.
Non-disjunction refers to the event in which the homologous chromosomes or sister chromatids fail to separate properly during a cell division.
In Down syndrome, the sister chromatids of chromosome 21 fail to separate properly which results in the formation of a gamete with 2 copies of chromosome 21.
When this gamete fertilizes with another gamete, it results in the formation of a zygote with 47 chromosomes, that is, 46 chromosomes + extra copy of chromosome 21.
Answer: from 30% sucrose solution to the 40% sucrose solution
Explanation:
From the definition of osmosis is the movement of water molecules through a selectively permeable membrane from a region of lower solute into a region of higher solute concentration, until the solute concentrations on the two sides is equal.
Therefore the net movement of water molecules will move from 30% sucrose solution to the 40% sucrose solution until the concentration of sucrose on both sides of the impermeable membrane is equal 35% each.
Facillatated diffusion is faster than simple diffusion when solute concentration is low because it uses channels to transport molecules throught the lipid bilayer. Simple diffusion depends upon concentration gradients so the net movement of diffusing molecules depends on the concentration gradient, thus the rate of diffusion is directly proportional to the concentration gradient.
Answer:
Helium
Explanation:
We know that this atom has two positive particles on the nucleus (protons) with two neutral particles (neutrons). We can also see that it hass two electrons on the orbitals. Knowing this, we can say that the element is Helium.
Helium has a relative atomic mass of 4 and it's atomic number is 2. The atomic number is equal to the number of protons and electrons the atom has, and the atomic mass can be used to calculate the number of neutrons:
Relative atomic mass = Neutrons + atomic number
So we know that:
Neutrons = relative atomic mass - atomic number
Neutrons = 4 - 2 = 2.
