DNA contains instructions for how cells come together
Answer:
DNA can be described as the molecules which carries the genetic code for every individual. The DNA is made up of nucleotide bases which join the two strands of DNA. The sugar and phosphate form the backbone of the DNA.
Genes are the hereditary molecules which are made up of DNA. The alleles of a gene represent which traits will be carried by an organism.
Chromosomes are made up of genes. During reproduction, crossing over of DNA occurs and alleles of the genes assort independently due to which variations occur.
Answer: A. The genes encode resistance to antibiotics.
D. The genes are carried on plasmids
F. The "clock"genes are highly mobile between species.
Explanation:
Molecular clock is a tool that is used to calculate the time of the evolutionary events. These are the gene sequences that are used to determine the evolutionary distance between the new and primitive organisms developed on earth. It also measures the random changes just like mutation. Thus the molecular clock is also called as the gene clock or evolutionary clock.
The accuracy of the molecular clock can be increased by the genes that encode for a resistance against the antibiotics, the genes that are carried on the plasmids and the clock genes which are highly mobile among the species.
Answer:
1. gravel of the sand: a part is dissolved and the remainder is grouped at the bottom of the beaker.
2. drop of sunflower oil: It is not absorbed and heaps on the surface of the water contained in the beaker.
Explanation:
Gravel of the sand is a polar substance. This means that this substance has the ability to dissolve and mix with water in a system in which both were placed together, such as a beaker, for example. However, the beaker limits the amount of water, which limits its ability to dissolve polar substances. Therefore, depending on the quantity, the gravel of the sand, when placed in a beaker with water, will dissolve, in parts, what is not dissolved will accumulate in the bottom of the beacker, because the gravel of the sand is denser than the water.
With the drop of sunflower oil the exact opposite happens. This is because drops of oil are nonpolar substances, which means that they do not have the ability to be dissolved in water. This means that when dropped into the beaker with water, the drop of sunflower oil will not dissolve, but will pile up on the water surface, because it is less dense than water.
