<span>the cell is the basic unit of a living the</span> cellular level of an organism is where the metabolic processes occur and keep the organism alive that's why it is referred to the basic unit of a living thing
Answer:
The correct option is b. lower esophageal sphincter
Explanation:
The esophagus is the initial part of the digestive tract and its function is the transport of the alimentary bolus from the pharynx to the stomach, through the thorax and avoid the reflux thereof. It begins and ends in two sphincter structures, the upper esophageal sphincter and the lower esophageal sphincter, which separate it from the pharynx and stomach. The lower esophageal sphincter has two functions: relax during swallowing and prevent reflux of the gastric contents into the esophagus in the postdeglutory period. After swallowing, there is a relaxation of the lower esophageal sphincter, pressure dropping to levels similar to those of the gastric fundus, which allows the bolus to enter the stomach. This relaxation lasts a few seconds and is followed by a strong contraction that prevents backflow of food.
Answer:
300% - 400%
Explanation:
The cardiac reserve is in the range of 300 to 400 percent (300% - 400%
) in normal young adults, while this percentage can be increased to 600% in trained athletes
Answer:
A
Explanation:
From what I know this could be wrong, but in the four stages of natural selection, the first step is overproduction, the second step is adaptation, and the third step is competition or survival of the fittest. This means that only the organisms with the best adaptations for their surroundings will survive. COULD BE WRONG SORRY IF IT IS