factors affecting digestion Flashcards
What does the digestive system do?
-The digestive system takes food and fluids consumed, extracts nutrients from it, and then washes away any waste products
Describe the process of digestion
1)Teeth and jaw break down food and mix it with saliva which contains enzyme amylase that begins break down of starch
2)After swallowing, food enters the oesophagus. The food is squeezed along the oesophagus through process of peristalsis. Takes food 3-6 seconds to travel to the stomach
3)Stomach acts as a large mixing bowl turning the food into a liquid called chyme. Stomach produces cells and juices containing enzymes and release hydrochloric acid which help breakdown food and kill any bacteria present
4)Chyme passes to small intestine. It is mixed with more digestive juices, this time from the pancreas. Pancreas juice contains bile made by the liver as well as enzymes to further assist breakdown
5)Peristalsis continue to move the chyme through the digestive system to the large intestine and then eventually to the rectum 💩
How does the body absorb nutrients?
-As chyme moves through the small intestine minerals, vitamins, fatty acids and sugar are absorbed by the intestine
-The surface area of the wall of the small intestine is increased by villi- allowing for more absorption
-By the time the chyme reaches the large intestine, it is less fluid and has been reduced to mainly indigestible matter
How does the body regulate blood sugar levels?
-Insulin and glycogen are secreted by cells and regulate the use and storage of glucose by cells
-After consuming carbohydrates, starch and other larger sugar units are broken down into glucose, absorbed in the small intestine and enter the blood stream
-The pancreas monitors blood glucose level and once it rises above normal levels, it releases insulin into the blood stream - insulin causes blood to move from the blood stream into cells where it is used for energy
Water in the blood needs to be kept more or less constant to avoid cell damage. What does there need to be a balance between for this to happen?
-Amount of water gained from diet through food and drink through water produced by cellular respiration 😋🌭
-Amount of water lost from sweating, urine and breathing 😓💩
How does the body maintain water levels when you haven’t ate or drank in a while or been sweating a lot
-The hypothalamus in the brain will detect a drop in the amount of water in the blood and send a message to the pituitary gland to release more of the hormone ADH
-ADH will travel to the kidneys via the blood and cause tubules to reabsorb more water into the blood 💧💧
