Answer:
C. Osmosis
Explanation:
Osmosis is the net movement of solvent molecules, usually water, from a region of lower solute concentration to a region of higher solute concentration through a partially permeable membrane. Osmosis is a very useful for moving materials in and out of the cell.
Solutions are mixtures of solutes and solvents. The main aim of osmosis is for all the mixture part to be uniform and the solvent equally dispersed to all the part of the solution.
Osmosis is controlled to a large extent by concentration gradient.
Diffusion on the otherhand is the movement of molecules of a substance from one position to another.
Facilitated diffusion and active transport are just mechanisms for transport within a cell or a body.
Answer:
Made mostly of collagen, bone is living, growing tissue. Collagen is a protein that provides a soft framework, and calcium phosphate is a mineral that adds strength and hardens the framework. This combination of collagen and calcium makes bone strong and flexible enough to withstand stress.
It is C as to have freckles you have to have a dominant and recessive gene (can be worked out using a punnett square) as the child has 50% of not having freckles like his dad or 50% having freckles like his mom.
male genes(homozygous recessive)
f f
female F Ff Ff
genes
f ff ff
so ff is not having freckles and being homozygous recessive, or Ff having freckles and being heterozygous.
So the child is heterozygous so C
Magnesium Phosphate is the answer
Answer:
If a DNA molecule has 30% Adenine the percentage of the other bases is Thymine: 30% Cytosine: 20% Guanine: 20%.
Explanation:
When the percentage that a base has in a DNA molecule is given, the percentage of the other bases can be known using the Chargaff's base pair rule.
A DNA molecule has the information of the genome of a living being, according to a specific sequence of its nitrogenous bases adenine, guanine, cytosine and thymine.
Chargaff was able to establish that in a DNA molecule the ratio of purine : pyrimidine of 1:1, so there must be the same amount of thymine as adenine and a similar amount of guanine for the cytosine, taking into account the complementarity of bases.
Taking into account the law of the base pair, if in a DNA chain there is 30% of Adenine, in the molecule there is:
- <em>Adenine 30%.
</em>
- <em>Thymine 30%.
</em>
- <em>Cytosine 20%.
</em>
- <em>Guanine 20%.
</em>
- <em>Total ..... 100%
</em>
In this case, the <u>Chargaff rule is useful to determine the percentage of nitrogenous bases that exist in a DNA molecule, knowing the percentage of a single base</u>.