Answer:
Bacteriophages (phages) are viruses that infect only bacteria and do not infect mammalian or plant cells. Phages are ubiquitous in the environment. Phages or bacteriophages were chosen as a model system for their simplicity, as they only contained protein-coated nucleic acid. Alfred D. Hershey and Martha Chase (who were part of the bacteriophage group) in 1952 studying the infection of the bacterium Escherichia coli by the T2 phage show that the information definitely resides in the DNA. They used phage with either [32P] -labeled DNA or [35S] -labeled proteins to infect the bacteria. Immediately afterwards, they centrifuged the sample so that the infected bacteria remain in the pellet and the virus capsids (proteins) remain in the supernatant. [35S] is found in the supernatant, whereas [32P] is found in bacteria. After one cycle of infection, it was observed that when phage labeled in the [35S] proteins were used, only 1% of the radioactivity was incorporated into the progeny. But when phages were [32P] labeled, more than 30% of the radioactivity was in the progeny. They showed directly that what is transmitted from one progeny to another is the DNA and not the proteins, despite having first "diluted" in a bacterium.
Explanation:
Bacteriophages are viruses that infect bacteria in a specific way. Bacteriophages, like other known viruses, are found in an intermediate zone between living organisms and inert matter. Bacteriophages bind to the host pathogenic bacterium, introduce their genetic material, replicate inside it and destroy it. Hersey, along with his assistant Martha Chase, used phages because they knew that T2 phages were made up of 50% proteins and 50% nucleic acids and that phages entered bacteria and reproduced. As the progeny carried the same infection traits, the genetic material of this had to be transmitted to the offspring, but the mechanism was unknown. These scientists carried out an experimental work with the T2 virus, a bacteriophage that infects the bacterium Escherichia coli, which it reproduces by attaching itself to the outer wall of the bacterium, injecting its DNA into it where it replicates and directs the synthesis of the phage's own proteins. Phage DNA is encapsulated within proteins and produces phages, which lyse or disrupt the cell and release phage from progeny. They infected a culture of bacteria with radioactively labeled phages: the protein coat with sulfur (35S) and its DNA with phosphorus (32P). After infection, they separated the phages from the bacteria by violent shaking using a mixer (hence the name of the experiment). By centrifugation the much smaller phages remained in the supernatant and the much larger bacteria in the pellet. 85% of the radioactivity corresponding to DNA appeared in the pellet and 82% of the protein in the supernatant. This result supported the idea that DNA was the only component of the bacteriophage that penetrated the interior of the bacteria and, having the ability to form new phages, constituted the genetic material.
Answer:
The normal range of blood glucose is 70–120 mg/dL. A person has a blood glucose level of 170 mg/dL. Based on your knowledge of the endocrine system and hormones, explain the likely cause for the person's condition.
It could be as a result of high sugar intake which increases the individual's blood glucose level
Explanation:
From the assertion above, it could be deduced that the individual pancrease is no more functioning hence; no control of blood glucose level. Furthermore, the continuous intake of sugar or food materials with high sugar content contributes excessively to increase the blood glucose level in the body.
The correct answer is A.
Both DNA and RNA are types of nucleic acids. DNA stands for deoxyribonucleic acid , while RNA stands for ribonucleic acid.
Both DNA and RNA carry genetic information. However, DNA is chiefly responsible for storing and transferring genetic information whereas RNA acts as a messenger between DNA and ribosomes during the process of protein synthesis and directly codes for amino acids.
DNA is double stranded while RNA is single stranded.
DNA has thymine in its structure but RNA does not. Instead in place of thymine it has uracil.
Answer:
Alcoholic fermentation converts one mole of glucose into two moles of ethanol and two moles of carbon dioxide, producing two moles of ATP in the process.
Explanation:
Answer:
The correct answer is glands.
Explanation:
It is known that brain monitors movement, therefore, one can definitely correlate movement of muscles with the brain that comprises the role of sensory and motor neurons. When a stimulus is obtained by the sensory organs, it is transmitted by the sensory neuron to the brain and from their information is further conducted to the effector organs like muscles by the motor neuron. The glands are the group of cells, which takes part in the secretions when instigated by any particular hormone.
