Unit 2 Nutrition and digestion

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

Classroom map?

Please find your seat according to the classroom map

Biology 2nd grade

Welcome back!!

This year, you will learn:

- a lot (!) about how your body functions (f.e. eating, breathing, circulatory system, reproduction, etc.)

- about how the world around you functions and works together (f.e. why plants are so important for all animals on Earth, or how wolves influence the way a river flows)

What do you bring with you every lesson:

- workbook (start with workbook 2/3a, later on we will also use 2/3b)

- notebook (a4 or a5). We will use it to write down answers to exercises (from the book or others) and for making notes during.

- TTO notebook for difficult English words

- laptop --> we don't use it every lesson, so keep it in your bag

Questions?

First Bite of Biology

8 statements about food & nutrition

I will read some personal statements. If you agree, raise your hand.

Unit 2 Nutrition and digestion

Today

• Talk about 2.1 Nutrition and digestion
• Check homework test yourself 
• Make a summary of 2.1 
• or Work on your assingment of unit 1 respiration 
  

learning objective

• You can name the functions of nutrients in foods.
• You know 6 groups of nutrients with their functions and characteristics.

Nutrients: usable components in food (=voedingsstoffen)

Dietary fibre: all indigestible parts of plants (=voedingsvezels)

vegetable products

Animal products

Foodstuffs

Function of Nutrients

• Building blocks: grow/develop/repair
• Fuels: by combustion in cells to provide energy
• reserves: to store up
• protection: to stay healthy  

6 groups of nutrients

carbohydrates

fats

proteins

minerals

vitamins

Water

Carbohydrates

• includes: glucose, sugars, starch, glycogen
• at first they are used as fuel
• then: building blocks and reserves
• glucose high: converted into glycogen                                                                           and stored in liver and muscles.
• glucose drops: glycogeen converted into  glucose and released into the bloodstream

fats

• primarily used as fuel 
• also as buildingblock or reserves
• reserves are stored beneath your skin
• the subcutaneous fatlayer becomes                                                     thicker.
• mostly you eat more fat than you need

Te veel vet -> slechtere werking

Proteins

• Important buildingblocks: 
• for example when cytoplasm is formed
• as Fuel
• Which foodstuffs contains proteins?
• beans, yoghurt, cheese, eggs, red meat,                                     chicken, fish, tofu 

Food that contain a lot of protein

Water

• Your body is made up of 60% water
• has a key role in transporting substances around your body
• most substances can only be transported properly if they are dissolved  

Minerals (or salts)

- Buildingblocks. Like calcium for strong bones

- For protection

- not too much each day

Vitamins

• buildingblocks and protection
• without you will become ill
• consuming large quantities will make you ill as well

-A: producing skin and seeing well

-B12: Red bloodcells

-C: resistance

-D: Strong bones

2.2 the digestive system

digestive system

excists of an intestinal tract

to let nutriens be absorbed into the bloodtream

glucose, minerals, vitamines, water

proteins, carbohydrates, vets have to be digested first

digestion =  converting products to be able to absorb into the bloodstream

The route through the digestive tract:

1. oral cavity                            tongue and salivary glands
2. oesophagus
3. stomach
4. duodenum                         gall bladder, liver and pancreas
5. small intestines
6. large intestines                 appendix
7. rectum
8. anus

Enzymes

Peritalsis & peristaltic movement

What to do in class

• Make a summary of 2.1; including a table nutrients/function
• Make the exercises of 2.1

Homework next week: summary 2.1 

Today

• Discuss 2.3 Healthy food 
• Add your foodlist in the website or app; see page 40 exercise 2 of your workbook
• Make a food advice for your neighbour in his or her notebook
• Check and correct your work 2.1 and 2.2
• Did you make a summary of 2.3?
• Make the exercises of 2.3

2.3 the digestive organs 

the oral cavity, pharynx and oesophagus

what are the names of the glands together? what do they do?

• salvary glands produces salvia: containing water, enzymes and mucus

stomach

• circular + longitudinal muscle for constantly movement
• pyloric sphincter is a circular muscle who close off the stomach
• the gastric gland produces gastric juices: containing: water, enzymes to digest proteins and hydrochloric acid to kill germs  

• liver produces bile (gal)
• bile is temporarily stored in the gall bladder
• bile passes through the bile duct when necessary
• bile emulsifies fats to make it easier for enzymes to digest.

• The wall of the intestines contains intestinal glands. They produce intestinal juice.
• various enzymes digest carbohydrates, fats and proteins
• the wall is convoluted, the intestinal folds in turn have protrusions called intestinal villi. 
  
• the wall of the intestinal villi is very thin. nutrients can pass easily 

• direct after the small intestines the caecum. (blinde darm). 
• the protrusion is called the appendix.
• inflamed in appendicitis; the appendix will be surgically removed. 
• In the large intestine water is extracted from the pulp. 
• If not -> Diarrhea
• Only undigested residues left over
• Bacteria are able to digest some cellulose and turn is into glucose
• glucose is absorbed into the bloodstream.  
  

2.4 Healty food

• What  is the basis for healty eating?
• The basic for healty nutrition is variation
• Also the food has to be safe. Not contaminated with germs. 
• Food poisoning: germs, bacteria, chemicals

• omega 3 for your health
• containing harmful substances because of environmental pollution.
• Seespiracy: 2021 netflix 

Advice for healty eating

• Wheel of five: each part for                                                                     daily basis
• saturated fats: animal fat
• unsaturated fats: fish and                                                                           vegetable oil