The answer is B mutualism
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.
Mucous membranes line the passageways that open to the exterior of the body, including those of the respiratory, digestive, reproductive, and urinary systems in the body.
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue.
It is mostly of endodermal origin and is continuous with the skin at body openings such as the eyes, eyelids, ears, inside the nose, inside the mouth, lips, the genital areas, the urethral opening and the anus. Some mucous membranes secrete mucus, a thick protective fluid. The function of the membrane is to stop pathogens and dirt from entering the body and to prevent bodily tissues from becoming dehydrated.
One of its functions is to keep the tissue moist (for example in the respiratory tract, including the mouth and nose). It also plays a role in absorbing and transforming nutrients.
Mucous membranes also protect the body from itself. For instance, mucosa in the stomach protects it from stomach acid and mucosa lining the bladder protects the underlying tissue from urine. In the uterus, the mucous membrane is called the endometrium, and it swells each month and is then eliminated during menstruation.
Learn more about Mucous membranes here : brainly.com/question/26244782
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<span>Punctuated
Equilibrium/ Equilibria proposes that once species appear in the fossil record,
the population will be in the state of
little or absent morphologic change. This is called a state of stasis. The
theory further proposes that the population is confined to infrequent and
geographical rapid events when significant evolutionary change happens. The parent species will the split into two
distinct species. This process if called cladogenesis.</span>
