A-plant Vacuoles are the largest in plant cells.
Answer:
<u>Benefits</u>:
pesticides can keep harmful pests–such as rats, mice, ticks and mosquitoes–away from crops while also protecting the plants from weeds and diseases that have the ability to greatly reduce crop yield.
<u>Environmental impacts</u>:
Pesticides may move with runoff as compounds dissolved in the water or attached to soil particles. Runoff from areas treated with pesticides can pollute streams, ponds, lakes, and wells. Pesticide residues in surface water can harm plants and animals and contaminate groundwater.
Answer: Option A. "In front of the patient, pointing at his navel"
Explanation:
The X-ray of abdominal cavity is known as Abdominal x-ray. It has same principle as X-ray and uses ionizing radiation to take pictures of inner parts of abdominal cavity such as intestine, stomach, liver and spleen. it is used to diagnose patients with vomiting, unexplained pain, and nausea.
While diagnosing patient's abdominal cavity, x-ray technician position the camera in front of the patient, pointing at his navel in order to produce a frontal view of abdominal cavity.
Talking about a x-ray machine, it is a compact apparatus which can be taken to the patient in a hospital bed or the emergency room. The x-ray tube connects flexible arm which further extends towards the patient and an x-ray film holder (image recording) plate is placed under the patient.
The technologist will ask the patient to take position on the x-ray table or bed and will position x-ray machine over the abdominal area of the patient, in order to take the frontal view of abdominal cavity. The patient will be asked to hold their breathe to get a clear picture. The technician will turn on the x-ray machine that allows x-ray machine to produce a small burst of radiation which passes through the abdominal area and records the frontal view of patient's abdominal cavity. As a result, soft tissue shows up in shades of gray and air appears black while bones appear white on the x-ray, through which patient can be diagnosed.
Hence, the correct option is A "In front of the patient, pointing at his navel".
Answer:
a. + glucose, + lactose = On
b. - glucose, - lactose = Off
c. + glucose, - lactose = Off
d. - glucose, + lactose = On
Explanation:
Lac operon has both types of control, repressible and inducible.
Whenever glucose level is low in the cell, an enzyme known as adenylyl cyclase raises the level of cAMP which forms a dimer with CRP protein and they both act as activator of lac operon and cause expression.
Apart from this, when lactose is present in the cell, β-galactosidase enzyme metabolizes lactose to form allolactose which causes allosteric repulsion in the lac repressor and causes its removal from the operator. As soon as repressor is removed lac operon gets activated.
In wild type lac operons, the expression of lac operon occurs when glucose level is low in the cell and lactose is present but in this mutant presence or absence of glucose will not make a difference because CRP will bind Plac promoter independent of cAMP level i.e. activator CRP will work even in high glucose concentration. If lactose is present then lac operon will always express so in option 'a & d' lac operon will express but in option 'b & c' it will not express.
