Question

Ppt on digestive system for class 4

Answer 1

Answer:

Explanation:1. Introduction The digestive system is used for breaking down food into nutrients which then pass into the circulatory system and are taken to where they are needed in the body.

2. Functions of the Digestive System Ingest food Break down food into nutrient molecules Absorb molecules into the bloodstream Rid the body of indigestible remains

3. Introduction There are four stages to food processing: 1. Ingestion: taking in food 2.Digestion: breaking down food into nutrients 3. Absorption: taking in nutrients by cells 4.Egestion: removing any leftover wastes

4. MouthTeeth mechanically break down food into small pieces. Tongue mixes food with saliva (contains amylase, which helps break down starch). Epiglottis is a flap-like structure at the back of the throat that closes over the trachea preventing food from entering it.

5. Parts of the Digestive System Teeth: Grinds your food. Salivary Glands: Produce the saliva in your mouth. Tongue: Helps to push food into your esophagus.

6. Teeth  Four types of teeth: 1. Incisors 2. Canines 3. Pre – Molars 4. Molars Incisors Canines Premolar Molar

7. Biting and Cutting Incisor Grasping and Tearing Canine Grinding and Crushing Pre - Molar Grinding and Crushing Molar

8. The tongue is not only one muscle.  It is a group of muscles, and it is also what we use to taste food with.

9. Can you really “swallow” your tongue? Explain. No you can not. The reason is because of the thin layer of tissue that connect your tongue to the bottom of your mouth called the frenulum. Your tongue is also attached to the front and sides of the pharynx.

10. Anatomy of the Tongue

11. © British Nutrition Foundation 2010 Taste The tongue can detect five basic tastes: • bitter; • salt; • sour; • sweet; • umami. Taste may be described by association with a particular food, e.g. meaty, minty or fruity. The intensity can also be recorded, e.g. mild or strong Cheddar.

12. © British Nutrition Foundation 2010 What is umami? Umami is a savoury taste, often known as the fifth taste. It is a subtle taste and blends well with other tastes. It was discovered by Dr Kikumae Ikeda, from Tokyo Imperial University, Japan, in 1908. He undertook research into Dashi, a traditional Japanese stock made from kombu (kelp). Umami has its own distinct savoury taste, often associated with ripe tomatoes and cheese.

13. When you look at your tongue in the mirror you can see raised areas or “bumps”. What are these raised areas called? These raised areas are called papillae.

14. 8. Name and describe the 3 different types of papillae. The 3 different types of papillae are: fungiform which are the larger ones located in the front of the tongue; filiform which are the smaller ones in the front; vallate which are the large ones in the back, there are only 8 to 10 of these.

15. Papillae have 2 purposes. Describe them. The purpose of the papillae is to grip the food and with the taste buds they contain.  They also “taste” the food.

16. What is the difference in the structure between a younger person’s tongue and an older person’s tongue? How does this affect the sense of taste? A younger person has more taste buds than an older person, about 2 times as much. The reason for this is because as a person gets older the taste cells don’t get replaced like they do when you are younger.

17. So, can you actually see taste buds with the naked eye? Explain. No, you see the papillae, and within the papillae are the taste bubs, and about 100 receptors or “taste” cells make up each taste bud, so you actually see many in one papillae.

18. The Human Digestive System  The tongue pushes food around until it forms a ball called a bolus.  The bolus is passed to the pharynx (throat) and the epiglottis makes sure the bolus passes into the esophagus and not down the windpipe!