Answer:
b. actively transport Cl- from the ECF to the external environment.
Explanation:
Chloride cells are cells that are found in the gills of teleost fishes which pump large amount of sodium and chloride ions out from the extracellular fluid (ECF) into the sea or environment against a concentration gradient in marine fish.
The opposite of this process occurs in freshwater fishes where the gills of freshwater teleost fish, cause an influx of sodium and chloride ions into the fish from the environment, also against a concentration gradient.
Mechanism of action
Salt water teleost fishes take in large amounts of seawater to decrease osmotic dehydration. The excess of ions derived from seawater is thrown out of the teleost fishes through the chloride cells. These cells employs active transport on the basolateral (internal) surface to diffuse in chloride, which then is pumped out of the apical (external) surface, straight into the surrounding environment. Such mitochondria-rich cells are located in the region of the gill lamellae and filaments of teleost fish.
Semiconductor materials are ostensibly little band hole encasings. The characterizing property of a semiconductor material with pollutions that adjust its electronic properties controllably. Most ordinarily utilized semiconductor materials are crystalline inorganic solids.
Answer: A: Its fertile oases enabled farmers to grow enough food for themselves and for sale.
Explanation: The Arabia region is a region located within the Arabian desert. A desert is an area of extreme heat, often dry weather condition with barren lands that cannot support agriculture and food production. An oases on the other hand is a region of luscious, cultivate-able land within a desert.
Food is one of the most important basic needs of man and hardly can anyone survive without food for more than twenty days. Hence, the presence of oases within the otherwise dry environment of the Arabia region is a major protection against death from hunger.
Taking a closer look at other options, none of them guarantees food supply and income to the Arabia region unlike food production in oases. Hence, the fertile oases is really the most important factor that serves as protection in the region's history.
Correct option: A
Answer:
active transport
Explanation:
it involves movement of ions
Complete Question:
Which of the following might stimulate the cephalic phase of gastric secretion?
A. stomach distention
B. the production of saliva
C. the thought of food
D. the production and secretion of gastrin.
Answer:
C. the thought of food
Explanation:
Gastric secretion usually occurs in three different phases, namely;
- Cephalic
- Gastric
- Intestinal
The thought of food usually stimulate the cephalic phase of gastric secretion in organisms. The presence of lipids or low pH inhibits Gastric secretion during the intestinal phase.
