Answer:
concentration gradient
Explanation:
concentration refer to number of ions on either side of membrane
gradient :difference in concentration on both sides of membrane
on this basis:
one side of membrane: higher concentration of h+ ion
other side of membrane :lower concentration f h+ ions
pumps transport ions from higher concentration side to lower concentration side of membrane
Answer:
adenine pairs with Thymine and guanine always pairs with cytosine respectively
Explanation:
In DNA nucleotide subunits, there are four nitrogenous bases:
- Adenine (A)
- Thymine (T)
- Cytosine (C)
- Guanine (G)
Each of these bases can be divided into two categories: purine bases and pyrimidine bases.
Adenine and guanine are examples of purine bases. This means their structure is a nitrogen-containing six atom ring joined with a nitrogen-containing five atom ring that share two atoms to combine the two rings.
Thymine and cytosine are examples of pyrimidine bases.
Note that RNA replaces thymine with a different pyrimidine base called uracil (U).
The complementary base pairing rule, Chargaff's rule states that DNA base pairs are always adenine with thymine (A-T) and cytosine with guanine (C-G). A purine always pairs with a pyrimidine and vice versa. However, A doesn't pair with C, despite that being a purine and a pyrimidine.
This was a major breakthrough in geology because it meant that sedimentary strata in diverse parts of a country or area could be correlated as belonging to the same formation which means they were formed at the same time historically so helped to put them in the correct sequence. If these strata contained valuable minerals like coal then it could aid in the search for coal. This helped William 'Strata' Smith in England to create his first geological map in the world of a whole country.
B. Carbon fixation begins the Calvin Cycle.