The answer is protect the body from infection by pathogens
The physical barrier is made of epithelial cells, mostly will be keratinized to increase their sturdiness further. They will impede the pathogen physically by barricading the cells, makes the pathogen could not invade deeper part of the body. Histamine and antibodies should be the role of immune cells, not epithelial.
Answer:
The primary function of glucose molecules is to provide energy for cell activities.
Explanation:
Glucose can best be described as carbohydrate which serves best as a primary fuel. Our body cells carry out a wide number of metabolic as well as biological functions. Glucose serves as the main energy derivation molecule for the accomplishment of these biological and metabolic functions. Every cell present in the body acquires the capability of using glucose as energy molecule.
Glucose is broken down by complex biological reactions into ATP which is the energy source for many cellular activities.
Answer:
The colonies are carrying the resistance genes from plasmids
Explanation:
Bacteria can acquire beneficial characteristics that they didn’t have. One way for these is through plasmids, which ones are little fragments of DNA that usually contains resistance genes (for antibiotics, disinfectants, heavy metals, etc.) or other capacities, like the ability to use some substances (for example sugars).
In this specific situation, we already know that the plasmid carrying genes for tetracycline resistance and the <em>lacZ</em> gene.
A little explanation:
Tetracycline is an antibiotic that inhibits bacterial growth and kills the bacteria. The bacteria can “fight” to this antibiotic if it has a resistant gene, the result is that the antibiotic can’t affect the bacteria and survive. An analogy is like a Police Officer (bacteria) that have a bulletproof vest (tetracycline-resistant gene) so the bullets (tetracycline) didn’t affect the police.
In the case of X-gal, is a compound consisting primarily in one sugar called galactose. Not all bacteria can eat galactose, they need an enzyme called β- galactosidase (comes from <em>lacZ</em> gene) that helps the bacteria “eat” the sugar (cuts the sugar in little pieces so the bacteria can eat).
Then, as the bacterial colonies can grow in the medium with tetracycline and X-gal, we know that those bacteria are carrying the resistance genes for tetracycline (does not affect the bacteria) and the <em>lacZ</em> gene (bacteria produce β- galactosidase that cuts galactose). These genes are coming from the plasmids because we already know that the plasmid carries these genes and not from the exogenous DNA.
Answer:
Serpentine minerals are made of tiny sheets of silica tetrahedrons that are loosely held together.
