Answer:
Because DNA polymerase can synthesize DNA strands in 5' to 3' direction only.
Explanation:
The 5' end of one DNA strand is present opposite to the 3' end of the other strand. But DNA polymerase enzyme can elongate the primers in 5' to 3' direction only. Formation of a phosphodiester bond between the existing nucleotide and the incoming nucleotide requires the free 3'OH. This 3' OH serves in the nucleophilic attack during the formation of the bond.
Therefore, the lagging strand is synthesized discontinuously in the form of short DNA fragments. These are called Okazaki fragments. Primers are formed for short distances which in turn are elongated by DNA polymerase to form the Okazaki fragments. On the other hand, the synthesis of the leading strand occurs continuously in the same direction in which the replication fork moves.
Tobias drank from a contaminated water fountain
Answer:
Threonine has two chiral centers.
The correct options are c. carbon b and d. carbon c
Explanation:
Chiral centers are those that have four different groups of atoms bonded to it. Carbon a has three atoms of hydrogen attached to it so it can't be a chiral carbon. It isn't the carboxyl carbon either since it is double bonded to oxygen. And the amino nitrogen does not qualify anyway because it is bonded to three different groups of atoms, not four.
Water Cycle:
1. It is stored in the ground.
2. Evaporation, transportation, precipitation
3. Runoff comes straight from precipitation. Infiltration is from the ground while run off never went in the ground.
4. It will usually end up in the same place, the ocean
5. Water levels rise, temperatures rise, CO2 in atmosphere increases
Carbon Cycle:
1. Carbon is important because it is one of the basic building blocks of life.
2. Trees, animals, grass, decomposition, combustion, fossil fuels
3. Carbon enters as photosynthesis.
4. Carbon enters water to the soil decomposition. Aquatic plants have plenty of water to work with, so their main challenge is getting enough sunlight and air.
6. By breathing in the oxygen from plants.
7. Two ways carbon return from animals into water is through cellular respiration and decomposition.
8. Combustion is when we dig up the fossil fuel and burn it, then what is left goes into the air starting the cycle again.
9. Deforestation reduces the capacity of forests to be carbon sinks.
Nitrogen Cycle:
1. Nitrogen is important because it helps us grow crops, and it produces grass for animal.
2. It comes from lightning and is named nitrogen fixation.
3. Ammonification and then transitions into nitrification and then to assimilation.
Phosphorus Cycle:
1. It forms part of life sustaining molecules like DNA and RNA.
2. Phosphorus is never found in the atmosphere.
<span>The answer should be 67.5gram
If Mary wants to consume 15% of her kcalories from protein, then the target calorie would be: 15% * </span><span>1800 kcal= 270kcal.
Every gram of protein will give about 4 kcal of energy. So, the protein needed in gram would be: 270kcal / (4kcal/gram)= 67.5 gram</span>
