Answer:
At the very bottom
Explanation:
When examining a cross section of rock layers, the oldest layer is on the bottom. This is because over time, newer rock layers continued to form on top of the oldest one.
For obtaining an adequate amount of DNA samples for DNA fingerprinting, polymerase chain reaction (PCR) can be used.
Polymerase chain reaction (PCR) is a technique that is used to amplify the DNA sample. The steps included in PCR are:-
1. Denaturation of the double-stranded DNA (at around 95°C)
2. Annealing of the primers to each of the single-stranded DNA templates ( at around 65°C)
3. Extension or elongation of the primers by considering every single-stranded DNA as a template. This elongation is carried out by <em>Taq </em>polymerase (at around 72°C).
With each cycle of PCR, the DNA sample is increased by 2ⁿ. Here, 'n' represents the number of PCR cycles.
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brainly.com/question/11442887
Answer:
Ion pumps can be distinguished from ion channels on the basis that ion pumps actively transport ions against a concentration gradient, while ion channels allow ions to passively flow down a concentration gradient.
Explanation:
Birth and immigration
death and emigration
Sugars are molecules that have a 1:2:1 c:h:o and are called carbohydrates.
