Answer:columnar describes cell shape.
Simple describe the number of layers
Explanation: epithelial tissues are one of the four major tissues of the body.the others being nervous, muscular, connective tissues.
Epithelial tissues are made up of thin cells that cover the external and internal surface of the body.
The cells may form one layer or more and they occur in several shapes.if they form one layer ,it is called simple.if they form several layers,it is called stratified.
Some are called pseudo-stratified because the cells occur with varying lengths and give the impression of stratified but they are actually made up of one layer.
Simple columnar epithelium is a single layer of tall, closely packed cells. They possess cellular extensions ,such as microvilli in the small intestine, or the cilia in the female reproductive tract.
Answer:
#1 false its difficult but also possible. #2 true and #3 False. the Salivary gland in the mouth make 1.5 liters a day
Answer:mutualism
Explanation:
In a mutualistic relation,both organisms involved benefit from the activities of each other. The benefits may be nourishment,shelter, protection etc.
In the above example,the birds are known to guide humans by responding to specific calls made by the human. They guide humans to beehives and then in return gets to feed on left over honey. Both the bird and human benefits by getting nourishment.
Mutualism is unlike parasitism where one of the organism involved benefits and the other organisms Is most likely harmed. It is also not commensalism, where one organism benefits and the other neither benefits nor is harmed