Answer:
Air particles are a mixture of solids and liquids that are microscopically tiny and suspended by air currents. It can stay in the atmosphere for a few hours to a month or two. Their constituents can be various harmful substances such as heavy metals - lead, nickel, arsenic, cadmium or polycyclic aromatic hydrocarbons
Explanation:
Air particles, nitrogen dioxide and ground-level ozone are now considered to be the three most polluting substances in human health. Exposure during peak concentration and long-term exposure to these pollutants can cause damage from respiratory distress to premature death.
The surface area of a sphere can be approximated as follows: Surface area = 4πr2; where r is the radius of the sphere; π is a constant that is roughly equal to 3.
Answer:
a. The operon is under positive control
a.) Loss of enzyme synthesis results from loss of regulatory R gene product which is regulated in the presence of Tis ophane for transcription. Absence of (Tis), transcription is positively controlled by regulatory Rprotein
b.) The proposed model reveals Tis / B complex prevents Tis enzymes from undergoing transcription through the RB operator by binding to the B region
the role of the R protein is
-decrease affinity of Tis / B complex to B region of RB
-bind to the R region on RB
- change the conformation of B region
- yield decreased affinity of Tis / B complex when R gene is lacking preventing transcription in the process
Effects of the RB mutations is that R protein will not bind to Tis / B complex to reduce transcription
Answer: The bacteria break down organic material that contain nitrogen and release it back into the cycle.
For example, bacteria breaks down a leaf, then it will release the nitrogen into the soil for plant.
The answer is C, since antibiotics will not effect viruses, only bacterial infections.
