2. What is digestion? How many types of digestions are there? Name them and explain their differences.
Digestion is the process by which food is transformed into simpler substances (nutrients), so they can be used by our cells.Mechanical process: such as chewing and the muscular action of the organs that contribute by crushing and mixing foods with digestive juices.Chemical process: performed by digestive enzymes found in the digestive juice. When these enzymes mix with food it produces a chemical reaction that breaks the food into simple substances.
3. Identify in which part of the digestive system the digestion is mechanical and the digestion is chemical
Chemical: stomach, liver,small and large intestine.
4. What is swallowing? Describe the three main stages
Is a process that allows the substance to pass from the mouth to the pharynx.
1.The bolus is driven to the oral cavity when the tongue pushes itself against the palate.
2.A series of reflexes makes the palate close the nasal passage, the larynx rise, and the epiglottis close its upper orifice. The bolus enters the pharynx
3.Another reflex helps the bolus to pass into the oesophagus
5.What are the peristaltic movements? Why are they important? Where does it take place?
The peristaltic movement is the contraction of two layers of muscle found in its walls for the bolus downward in the oesophagus
Is important because without this the bolus can’t move to the oesophagus were it take place
6. Don’t forget to explain how the digestion in the stomach is. What substances or molecules are in the stomach digestion involved? What nutrients are digested in the stomach, and in the mouth?
First the bolus enter in the stomach and its muscles start to contact and mix with the gastric juices
Pepsin (an enzyme) starts proteins digestion, breaking proteins dow the small fragments that his process make are called peptides
Hydrochloric acid has two functions.
Activate pepsin enzymes and support them by helping the disintegration of food fibres
It destroys bacteria that are in food, after food is mixed with gastric juices its transformed into chyme. The three muscular layers of the stomach mix chyme
When it reaches a high level of acidity, the pylorus opens and the chyme enters to the small intestine and
7.Explain how the digestion in the small intestine is. Organs which are involved, like pancreas and liver and the enzymes which act on the digestive process.
After the pylorus opens, the chyme travels from the stomach to the small intestine, once here chyme mixed with digestive secretions released by the small intestine, as well as secretions from pancreas and the liver.
8. What is the absorption? Where does it take place? What structures does the intestinal wall have for increasing the absorption of nutrients?
It's the passage of nutrients to our blood. This allows the nutrients to be distributed across the whole organism
9. What are the main parts of the large intestine? Name them and explain their main functions
The cecum, its main function is to absorb fluids and salts that remains after completion of intestinal digestion and to nor its contents with mucus
The colon, it symbiotic bacteria of intestinal flora develop
The rectum, indigestible food ingredients are decomposed by anaerobic bacteria.
2. What is the gas exchange?
Is the change between the air of the environment and the blood of the organism
Where does it happen? Explain it.
It happen in the pulmonary alveolus that are connected to the venula, it is connected to the bronchioles that are in the extreme of the bronchus and they made up the lungs
3. What is pulmonary ventilation?
Is the change of the air inside the lungs by the air in the environment.
How many processes are involved in the pulmonary ventilation?
Inspiration, in which the air enters the lungs the ribcage increases its volume and the diagram contracts, flattens and lowers itself.
Expiration, in which the air exits the ribcage decreases its volume and the diagram relax, flattens and lowers itself.