Explanation:
guessing :
a. The oxygen atom in a water molecule has a slight negative charge.
Answer:
1. Many vertebrates have teeth, and chewing (mastication) breaks up food into small particles, expanding its surface and mixes it with fluid secretions, which makes it possible to digest. Teeth are located in the mouth of animals, where the digestive process initiates.
2. The stomach, which resembles a bag-like shape, can either fold up when empty and expand like a balloon when it fills up with food. By doing this, the area of activity of the gastric juice is expanded, increasing the efficiency of the digestion. Food enters the stomach from the esophagus.
3. The villi and microvilli present in the epithelial wall of the small intestine, are fingerlike projections that greatly enhance the surface area of the small intestine. In humans, this surface area is 300 square meters and it is over this large surface that the products of digestion are absorbed.
Answer:
B. Interneurons
Explanation:
The basic unit of the central nervous system is the neuron or the nerve cells. Billions of neurons allow the different parts of the body to communicate with each other via the brain and the spinal cord. A fatty material called myelin coats nerve cells to insulate them and to allow nerves to communicate quickly.
Answer:
B. When limiting factors and interactions of organisms create balance within a community.
It means that it's a living organism. As opposed to abiotic, which isn't a living organism.