Answer:
Any technological application using living things or living systems is called Biotechnology.
Explanation:
It is essentially genetic engineering which involves technological applications of living things.
The hydrogen ion concentration of a solution is indicated by its <u>pH </u>value.
Explanation:
- A measure of acidity or alkalinity of water soluble substances (pH stands for 'potential of Hydrogen'). A pH value is a number from 1 to 14, with 7 as the middle point.
- Under normal circumstances this means that the concentration of hydrogen ions in acidic solution can be taken to be equal to the concentration of the acid.
- The pH is then equal to minus the logarithm of the concentration value.
- Values below 7 indicate acidity which increases as the number decreases, 1 being the most acidic.
- The pH of a solution is a measure of hydrogen ion concentration, which in turn is a measure of its acidity.
- Pure water dissociates slightly into equal concentrations of hydrogen and hydroxyl (OH−) ions. For a neutral solution, [H+] is 10−7, or pH = 7.
Answer:
I think you're referring to the Metaphase...
Explanation:
During Cell Division (or, rather before!) the DNA needs to be replicated. This normally is done by DNA Polymerase, and results in two identical double strands (the "Sister Chromatids".
These chromatids are held together at the Centromere, which will be the heart of the "X"-shape. After that the DNA is packed into Chromosomes by winding it around proteins called Histones. If I remember correctly there are 5 different Histones.
This "Zipping Up" makes the chromosomes more visible.
As the two sister chromatids are still connected, the result is the X-shaped Metaphase Chromosome....
The structure of DNA is called a double helix because DNA is made up of two strands of nucleotides wound together in a spiral.
DNA has two strands that run opposite of each other and twist together much like a twisted ladder. Each backbone of the ladder is made up of alternating groups of sugar and phosphate groups.
