Answer options:
- extraction and observation of DNA
- identification of ribose and deoxyribose
- recognition of RNA as DNA’s messenger
- construction of an accurate DNA model
Answer:
- identification of ribose and deoxyribose
Explanation:
Phoebus Levene was an American biochemist who studied the structure of DNA and RNA. He was able to isolate the sugars (ribose and deoxyribose) from the nucleic acids, which are an important part of their structure.
He also determined how the nucleic acid components combine to form the nucleotides, the basic building blocks of nucleic acids, and how the nucleotides combine in chains to form the polymer.
The answer is b mass because that's how you will measure it
Answer:Radiometric dating allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata. The correct option is D.
Explanation:
Radiometric dating was first used by geologist after being published by Bertram Bollywood in 1907. During volcanic eruption, some minerals ( carbon) are trapped within the volcanic strata. These minerals are made up of radioactive isotopes which are unstable as they form decay products with a known constant rate of decay. This enables them to :
- access information about the absolute age of rocks,
- date a wide range of natural and man-made materials
- know even the age of earth. I hope this helps. Thanks
Explanation:
Much energy is demanded within a short period in a sprint as opposed to long-distance that mainly demands stamina. During sprints, therefore, the energy demands by the muscles my outpace the supply by energy because oxygen is not reaching fast enough for aerobic cellular respiration. This is why sprinting cannot be sustained for long without accumulation of lactic acid in muscles – due to glycolysis metabolisms being the main source of energy.
IN long substance however, the runner does not sprint the entire marathon but run at sustainable speeds allowing the energy demands by the muscles to be met by the more effective aerobic respiration
