After passing through the cornea, light travels through the pupil (the black dot in the middle of the eye). The iris—the circular<span>, colored area of the eye that surrounds the pupil—controls the amount of light that enters the eye.</span>
Answer:
True
Explanation:
Physical contamination are foreign objects such as hair, fingernails, broken glasses , jewelries etc that are mixed with food. Although, it is important for a food handler who realizes that he is sick such as having fever, jaundice,wound while working to report such to his supervisor or manager,who will then take necessary action and to avoid risk of contamination; yet not the only cause of physical food contamination.
Physical contamination does not necessarily have to occur until the food handler is sick. It could be as a result of carelessness or not paying attention enough by the food handler . Physical contamination might not at all times cause injury or illness to the customer, yet such could bring discomfort to a customer who notices foreign objects in his food while eating. To avoid risk of physical food contamination, it is important for food handlers to keep jewelries to a minimum, wash fruits and vegetables thoroughly, wear hear neatly tied back, throw out and replace cracked, chipped, or broken dishware, glassware and equipment amongst others.
Covalent bonds are formed when two atoms are able to <em>share</em> electrons.
Iroinic bonds are form when two atoms are <em> </em> electrons from each other to complete the bond. This results in a pair of ions.
<u>Covalent bonds:</u>
- Have a definite shape.
- Have a low melting point.
- At room temperature they are in a liquid or gas.
- They occur between two non-metals.
<u>Ionic bonds:</u>
- Have no definite shape.
- Have a high melting point.
- At room temperature they are solid.
- They occur between a metal and a nonmetal.
Answer: DNA ligase.
Explanation:
Polymerase chain reaction is a technique used in molecular biology by scientists to make several copies of a DNA sample which enable them to take a smaller portions of it and expand it for more detailed study.
PCR mixture is premixed and contain thermostable DNA polymerase, oligonucleotides primer, four deoxynucleodide triphosphates, Magnesium chlorides, a propietary buffer.
