Hi,
Harshey and Chase did a great experimentation which was basically a two step experiment to prove that DNA and not proteins are the actual carriers of genetic information from parents to offspring.
- In the first part of their experiment, they used bacteriophages (virus that eat bacteria). They used radioactively labeled sulphur(35S) medium to grow bacteriophages and observed that all the bacteriophages had proteins with radioactive sulphur(35S).
- In the next step they allowed these phages to infect bacteria and to their surprise, they found that the bacteria did not had radioactively labeled sulphur in them because the coat of bacteriophage stays outside the body of bacteria when it attacks it. This proved that DNA not proteins were the hereditary material.
- To make their results more reliable, they did a second experimentation in which, they marked the DNA of the phage with radioactive phosphorus 32P. After labeling DNA, they repeated the same experiment and this time, they found radioactive phosphorus inside the bacteria.
<em>This meant that the bacteria had DNA of phage entered inside them and this again proved that DNA not proteins are the hereditary material. You can see attached image for better understanding.
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Hope it help!
Answer:
A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable.
You have ligaments around your knees, ankles, elbows, shoulders, and all of your other joints.
Ligaments are bands of tough elastic tissue around your joints. They connect bone to bone, give your joints support, and limit their movement. Ligaments are made out of connective tissue that has a lot of strong collagen fibers in it. They are found in different shapes and sizes in the body. Some look like pieces of string, others look like narrow or wide bands. There are arch-shaped ligaments, too.
Explanation:
Nucleotide bases are added to DNA strands in a 5' to 3' direction.
What is DNA replication?
When a cell divides, DNA copies itself through a process called replication.
- Generally speaking, DNA replication involves uncoiling the helix, strand separation by rupturing the hydrogen bonds between the complementary strands, and synthesis of two new strands through complimentary base pairing.
- The origin of replication, which is a precise location in the DNA, is where replication starts.
- From the point of origin, DNA replication is bidirectional.
- The two parent DNA strands unwind and split apart at the origin of replication to generate two "Y-shaped" replication forks in order to start DNA replication.
- These unwinding enzymes are known as DNA helicases.
- The real location of DNA copying is at these replication forks.
- Proteins that destabilize helices bind to the single-stranded areas to prevent the two strands from rejoining.
- To reduce stress on the helical molecule during replication, enzymes known as topoisomerases cause breaks in the DNA and then reunite them.
- The hydrogen bonding of free DNA nucleotides with those on each parent strand results in the formation of new complementary strands as the strands continue to unwind and split in both directions around the entire DNA molecule.
- The new nucleotides are joined by DNA polymerases using phosphodiester bonds as they align themselves opposite each parent strand using hydrogen bonds.
- Deoxynucleotide triphosphates, which are made up of a nitrogenous base called deoxyribose and three phosphates, are the actual nucleotides that are aligning through complementary base pairing.
- Two of the phosphates are withdrawn to provide energy for bonding as the phosphodiester bond forms between the 3' OH of the previous nucleotide in the DNA strand and the 5' phosphate group of the next nucleotide.
- In the end, two identical DNA molecules are created when each parent strand acts as a template for the synthesis of a complementary copy of itself.
Hence, nucleotide bases are added to DNA strands in a 5' to 3' direction.
To learn more about DNA replication click on the link
brainly.com/question/21265857
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50% of the offspring would have a feather color that results from incomplete dominance.
Answer:
plants animals and cosmic rays