science interactive ltdmrwaynescience.weebly.com/uploads/9/6/0/5/9605754/the... · 2018. 10....

Science Interactive LTD

Science Interactive LTD. PO BOX 50764 LONDON NW6 9AT email: [email protected] web: www:science-interactive.co.uk

Science Interactive LTD Copyright 2005

Science base multimedia CD-ROM for PC is a collection of 38 units or tools totalling over 1150 PowerPoint slides. Each unit covers a wide range of different delivery and learning styles, offering an exciting way to involve your pupils during lessons or revision sessions. All styles of teaching and learning are supported through use of high quality images, graphics, challenging exercises and questions. Units can be used in the classroom via an interactive whiteboard, data projector or used during individual study via a PC or school network.

Unit 19: The Transitional Metals

Unit 18: Metals and their Properties

Unit 17: The Alkali Metals

Unit 16: The Periodic Table and its Elements

Unit 15: Genetic Engineering

Unit 14: Evolution and Human Impact

Unit 13: Inheritance and Selection

Unit 12: Mitosis and Meiosis

Unit 11: Flow of Energy and Elements through the Environment

Unit 10: Water Transport in Plants

Unit 9: Photosynthesis in Green Plants

Unit 8: Drugs and Bad Body Maintenance

Unit 7: Hormones and the Endocrine System

Unit 6: Human Homeostasis

Unit 5: Nervous System and the Senses

Unit 4: The Respiratory System

Unit 3: Healthy Body and Immunity

Unit 2: The Circulatory System

Unit 1: The Digestive System

Unit 38: Cells, Tissue, Organs and Organs systems

Unit 37: Natural Forces

Unit 36: Sound and Hearing

Unit 35: The Alkaline Earth Metals

Unit 34: The Earth and Plate Tectonics

Unit 33: Earth and Space

Unit 32: Newton's Forces and the Effects of Forces

Unit 31: Radioactivity

Unit 30: Light and the Electromagnetic Spectrum

Unit 29: Electricity

Unit 28: Generating Electricity and its Domestic Use

Unit 27: Energy

Unit 26: Rates of Reaction

Unit 25: The Noble Gases, their Properties and Uses

Unit 24: The Halogens, their Uses and Compounds

Unit 23: Ionic and Covalent Compounds

Unit 22: Elements, Molecules and Compounds

Unit 21: Rock Cycle

Unit 20: Crude Oil and its Products


Unit 1The Digestive System

Unit 1: The Digestive SystemUnit 1: The Digestive System Science Interactive LTD Copyright 2005

Understand: Keywords:1. What are the seven food groups and their role

in a healthy balanced diet.2. The chemical tests to detect the presence of

proteins, lipids, carbohydrates or sugar in foods.

3. What the recommended daily amounts of vitamins and minerals are in a healthy diet.

4. The role of the digestive system and its key organs during the physical and chemical breakdown of food.

5. The role of enzymes during the chemical breakdown of foods.

6. How enzymes function as catalysts.7. The role of the villi tissue in the absorption of

nutrients from the gut into the blood. 8. The fate of these nutrients in the body and their

assimilation into cells and tissues.9. The health consequences of overeating and

under eating.10. The importance of getting the balance right.

Nutrition, Nutrients, Food, Groups, Fats, Carbohydrates, Proteins, Minerals, Vitamins, Fibre, Water, Digestive, System, Physical, Chemical, Villi, Breakdown, Absorption, Nutrients, Amino acids, Glucose, Fatty acids, Glycerol, Obesity & Malnutrition.

web: www.science-interactive.co.uk email: [email protected] Interactive LTD PO BOX 50764 LONDON NW6 9AT

Click mouse to begin


Overview of the digestive systemOverview of the digestive systemThe digestive system is a collection of cells, t________ and organs that function together to breakdown and absorb the daily essential nutrients, minerals and vitamins required for healthy growth and development. The digestive system is able to breakdown proteins, fats and carbohydrates prior to their absorption into the bloodstream. These large food molecules are broken down into smaller molecules by both physical and chemical d________. Name a cell, tissue and organ that belongs to the digestive system ?

The digestive system:

Anus

Rectum

Large Intestine

Small Intestine

Liver

Stomach

Oesophagus

Mouth

Organ

__________________________________ ?

__________________________________ ?

__________________________________ ?

__________________________________ ?

__________________________________ ?

__________________________________ ?

__________________________________ ?

Chews foods, using canines, incisors and molars.

Function (complete table)Diagram of the digestive systemWord bank: tissues digestion


Dietary intake of foodsDietary intake of foodsOur dietary intake of foods like proteins, carbohydrates and lipids should provide us with the correct amount of c________ energy to maintain our daily activities, growth (if we are children) and repair. An adult male requires about 10,500 kilojoules per day, equivalent to about 100 joules per second. This is the same energy that a 100 watt light bulb uses. Taking too much energy, by perhaps consuming too much raw sugar or fat, can lead to weight gain, high blood pressure and eventually o________.

Daily energy requirements: Word bank: chemical obesity

Growth & reproduction

Assimilation

Dietary energy Respiration

10,500 kJ/day (adult male)

C6H12O6

6O2 6CO2

6H2O

Mitochondria Energy

Respiration

All the chemical energy, vitamins and minerals that we require are provided by a balanced diet. Overeating or under eating, eating too little vitamins and minerals can cause many health problems in adults and children. It is estimated that one in four adults in the Britain will be clinically obese by 2010.

Notes

Diagram

Dietary intake, assimilation and respiration

Deficiency diseasesDeficiency diseasesYour diet needs to be b____________, providing all the necessary v_________ and minerals that you require for healthy growth and development. In some areas of the World, poor diets lacking in just one or two minerals or vitamins causes deficiency diseases. Scurvy is a good example of a deficiency disease that was common amongst sailors during the 17th and 18th

centuries. This disease was caused by a lack of vitamin C contained in fresh fruit and vegetables, then unavailable during the long sea voyages. Scurvy can lead to bleeding of gums and the general deterioration of muscles and joints.

Deficiency diseases:


Word bank: balanced vitamins

Scurvy: Gums begin to bleed and old wounds begin to open. Limes were carried and included in a sailors diet to avoid scurvy. Osteoporosis: A diet lacking in calcium leads to poor teeth and bone development. In older age, bones become weak and break easily. Ricketts: A lack of vitamin D causes soft bones during a child’s growth. This disease is known as rickets. Vitamin D is produced by the skin during the summer months. Night blindness This is a result of too little vitamin A in the diet.

NotesRickets

Vitamin D

Night blindness

Vitamin A

OsteoporosisScurvyDeficiency

Diagram

Vitamin C Calcium


A balanced dietA balanced dietThe amount of energy (kJ) we consume through our diet and the recommended daily amount of m________ and v___________ we need for normal healthy growth and development is given by the table below. Notice that these values depend on our age, our sex, when female if we are pregnant or lactating and even our lifestyles. The amount of e_______ we need can also depend on the type of job we have, for example a labourer digging roads will require more energy from their diet than someone who works in an office. Look at the information given by the table and answer the questions.

Daily vitamin, mineral and energy requirements:

140001512751.36563+200035Female (lactating)

130003010700.860+ 12+ 100035Female (pregnant)

12000158600.85063975035Female

12000158600.84455975015Female

10000101060163801050035Male

120001210601.159591250015Male

mgmgugmgmggkgkJYearsUnits

CalciumIronVit DVit CVit AProteinBody Wt.EnergyAgeSexWord bank: minerals vitamins energy

Questions: 1: Why does a 15 year old male require more energy than a 35 year old male.2: Why do females require more iron than males.3: What role does vitamin C and calcium play in the body.4: Why do you require less vitamin D in the summer when compared to winter.5: Why does a lactating female require the most protein in her diet.


Nutrition and food groupsNutrition and food groups oneone

There are seven basic food groups essential for a healthy d______. The three main food groups p________, fats and carbohydrates provide us with all the energy requirements as well as having specific functions in the body. Carbohydrates should make up about 55% of your total daily kilojoule intake. Too much fat in your diet can lead to blocked a_______ and obesity. Protein is required most during p_______ in adolescents for growth and repair. Compare the diets of a body builder, adolescent female and male and a pregnant female, how might they differ ?

Proteins, carbohydrates and lipids: Word bank: diet proteins arteries puberty

___________________________________________?

_______________________________________?

Animal flesh, Soya bean and nuts.

Sources

Converted readily to glucose by carbohydrase enzymes found in mouth saliva and the small intestine. Glucose is then respired in cells.

Carbohydrates

Store of energy. Insulates the body against the cold. High lipid diet lead to atherosclerosis and obesity. 1 in 5 adults are obese.

For growth and repair. During puberty protein demand is very high. Why do body builders take a high protein diet ?

Function

Diagram

Proteins Lipids


Nutrition and food groupsNutrition and food groups twotwo

The other four food groups, although they do not provide the body with any energy, are allessential for healthy g_______ and development. A balanced diet supplying all the necessary vitamins and minerals comes from eating a diet containing low fat meat, plenty of carbohydrates, fresh f_____ and vegetables. Many foods sold in supermarkets now have vitamins and minerals added to them, so that we can all take our recommended daily amount.

Vitamins, minerals, roughage and water: Word bank: growth fruit

_________________________________?

___________________________?

_____________________________?

All fresh fruit and vegetables.

Sources

Helps keep regular bowel movements. A low fibre diet increases the risk of contracting large bowel cancer.

Roughage

Correct hydration is essential for every cell and of course normal blood pressure. How much water should you drink every day ?

Water

Healthy tissue growth and development. A lack of iron causes anaemia of the blood. Low calcium affects bone growth.

Healthy tissue growth and development. Lack of vitamins leads to deficiency diseases like scurvy and rickets.

Function

Diagram

Vitamins Minerals


Food testsFood tests oneone

The presence of proteins, starch, sugars and l_______ in foods can be tested for by using ‘food tests.’ Scientists test foods for the presence of each of these food groups so they can provide nutritional information on their food products. Where is this information normally found on a packet of crisps or a chocolate bar ?

Food tests: Word bank: lipids

Control Positive Control Positive Control Positive

lipid food test

Paper goes clear with lipidsResult

Iodine testPlace 6 drops of iodine water on food sample.

Starch

Benedict's testAdd 5cm3 of benedict’s solution. Heat tube in hot water for 5 minutes.

Sugar

Paper testPlace a small amount of tested food on paper. Allow to dry.

Biuret’s testAdd 5cm3 of copper sulphate and 5cm3 of sodium hydroxide.

Test

Diagram

Protein Lipid


Food testsFood tests twotwo

Starch, a polymer of g_______ is found in many foods including all cereals and most vegetables. Starch is broken down by the carbohydrase e________ to glucose. In this form, glucose is readily absorbed and transported to the many billions of cells in the body. Glucose is oxidised with oxygen during cellular respiration to provide energy essential for life. Although glucose is essential for cellular respiration, which disease might you suffer after years of eating a high glucose diet ?

Testing for starch in foods: Word bank: glucose enzyme

Starch ?

YesNo

Apple

Starch ?

YesNo

Sucrose solution

Starch ?

YesNo

Starch ?

YesNo

Results

DiagramStarch solution Corn


Function of the digestive organsFunction of the digestive organs oneone

Each organ or tissue in the digestive system has a specific function that helps break down the three main food groups (proteins, lipids and carbohydrates) into small molecules so they can be a_________ into the blood stream. The majority of e___________ that chemically breakdown foods are released by the pancreas into the small intestine. After carbohydrate, protein and lipid breakdown, their products; sugars, amino acids, fatty acids and glycerol are absorbed across the villi into the blood stream. Why can only small food molecules like glucose cross from the gut into the blood ?Digestive organs:

Adds acid and proteases to begin protein breakdown. The stomach has a pH of around 2. This also kills any bacteria found in food.

Stomach

Most enzymes are found here. Lipids, proteins and carbohydrates are broken down before they are absorbed into the blood across the villi.

Small intestine

Sends contents to stomach by squeezing chewed food (bolus) This process is called peristalsis. Gravity also helps this process.

Chews food and secretes salvia which lubricates the food and contains the enzyme carbohydrase, which begins to break down carbohydrates.

Notes

Diagram

Teeth Food pipeWord bank: absorbed enzymes


Functions of the digestive organsFunctions of the digestive organs twotwo

All nutrients including amino acids and glucose and other food groups including water, minerals and vitamins are absorbed by the v______ found in the small intestine. The remaining organs of the digestive system including the large intestine and colon remove water from undigested material, helping to form a solid stool. The rectum stores the waste faeces until its excretion via the anus. Blood takes the nutrients to the l_______ where they are processed and sent via the circulatory system, the billions of cells in the human body.

Digestive organs:

The large intestine absorbs and recycles water. The stool begins to become solid. This makes it easier to store by the rectum.

Large intestine

The rectum stores the solid waste which contains undigested food (fibre), bacteria, water and broken down blood cells.

Rectum and anus

The pancreas is found behind the stomach. The pancreas makes and releases all the enzymes found in the small intestine.

Processes all nutrients like amino acids, glucose, fatty acids and glycerol. Also breaks down excess amino acids forming urea.

Notes

Diagram

Liver PancreasWord bank: villi liver


Physical digestionPhysical digestionThe breakdown of proteins, carbohydrates and lipids begins with chewing. Humans have a mixture of c_______, incisor and molar teeth which are designed to cope with a varied diet, which includes animal flesh and vegetables. Our canines and incisors tear and rip food. Our molars, with their flat profile are designed to grind and chew fibrous vegetable matter like root vegetables and fruits. How does a high sugar diet affect our teeth and lead to tooth decay ?

Human teeth and physical digestion: Word bank: canine

Modern toothpaste now contains fluoride which helps control oral bacteria and prevents tooth decay. Always have a 6 monthly check-up at the dentist.

Brushing

The tooth (incisors, canines and molars) are capped with white enamel. This is made from calcium carbonate and is the hardest substance in the body. It can be eroded by acids found in foods or produced by oral bacteria.

Humans have two sets of teeth. Your milk teeth are replaced when you are about eight years old. Your final molars appear in your twenties.

Notes

Diagram

Teeth Human teeth


Enzymes and chemical digestionEnzymes and chemical digestionDigestive enzymes break down large f_____ molecules into smaller ones. Enzymes are all proteins, and are very specific, only having one substrate like a protein or a lipid. They behave like c_________, able to speed up the rate of reaction and can be recycled by the digestive system. There are three main types of enzymes found in the digestive system: proteases, carbohydrases and lipases. Look at the table below to find out the function and location of each type ?

Types of digestive enzymes: Word bank: food catalysts lipases

Fatty acids and glycerolSugarsAmino acidsProducts

L_________-pancreatic

Lipids

Carbohydrases-salivary-pancreatic

Proteases-stomach -pancreatic

Enzymes

Diagram

Proteins Carbohydrates


How enzymes functionHow enzymes function oneone

For proteins, lipids and c____________ to be absorbed from the small i_________, into the blood, they must be broken down into small molecules. Digestive enzymes breakdown food chemically. An enzyme’s substrate will bind to the enzyme’s a_________ site where chemical bonds are broken producing smaller molecules which can then be absorbed into the b________ stream.

How enzymes break down food molecules: Word bank: carbohydrates intestine active blood

Substrates

Products

Substrate

Enzyme substrate complex

Products

Enzyme (catalyst)active site

Enzymeactive site

Enzyme (can be reused)active site

Step three

New products like glucose are formed which then leave the enzyme’s active site.

Stage three

Step two

Chemical bonds are broken by the enzyme to form monomers.

Step one

Substrates like proteins, carbohydrates and lipids bind to the enzyme’s active site.

Notes

Diagram

Stage one Stage two


Enzyme are biological catalysts which will increase the rate of b__________ of proteins, carbohydrates and lipids without be used up themselves. Enzyme catalysts are able to lower the activation energy required for new products like sugars and amino acids to be produced from substrates like carbohydrates and proteins. The reaction takes place in an area of the enzyme which is called the active site.

Enzymes as biological catalysts:

How enzymes functionHow enzymes function twotwo

Lower the activation energyNot used up during the reaction

Enzymes are biological catalystsCarbohydrases, Lipases, Proteases

Word bank: breakdown

active site active site

Carbohydrase + Carbohydrate

Catalyst Catalyst

Carbohydrase + sugar molecules

Carbohydrate Sugar

Sugar

Sugar

Sugar

Sugar

active site active site

Enzyme Enzyme

Notes

Diagram

Substrates like carbohydrates collide and temporarily bind to the enzyme’s active site on its surface. The bonds in the substrates are weakened by the enzyme. The bonds are broken and new products are formed. These products (sugar) then leave the enzyme’s active site, leaving the enzyme catalyst unchanged and able to participate in further reactions.

Breakdown of carbohydrates by carbohydrase

A human body contains many hundreds of different enzymes found inside cells and as part of the d_________ system. Without enzymes, which catalyse the breakdown of nutrients like proteins, carbohydrates and fats, digestion would be too slow to support all your functions. Like many of the inorganic catalysts, enzymes lower the activation energy and increase the rate of reaction without being used up. With enzymes, the rate of reaction increases as the t___________ increases, doubling for every 10oC rise in temperature. However, above approximately 40oC, enzymes are denatured or destroyed and will stop working altogether. Name three types of enzymes found in the human gut ?

Biological enzymes as catalysts:

With inorganic catalyst

With enzyme

0 Temp oC 40 60 80 100Ra

te o

f rea

ctio

n

Substrates with sufficient energy to form new products

Without enzyme

With enzyme

How enzymes functionHow enzymes function threethreeScience Interactive LTD Copyright 2005

Word bank: digestive temperature

As you increase the temperature by 10oC the rate of reaction doubles until around 40-45oC where the high temperature denatures or destroys the enzyme. Inorganic catalyst like iron and nickel are not temperature sensitive.

Heat sensitive enzymes

A catalyst will lower the activation required for substrates to react with one another to form new products. The graph above shows how by adding a catalyst, the activation energy shifts to the left increasing the number of successful collisions and therefore increasing the rate of reaction. Enzymes are highly specific for their substrate.

How enzymes speed up the rate of reaction


Using enzymes as catalystsUsing enzymes as catalystsEnzymes are used in a wide variety of industrial applications. Enzymes found in yeast cells are used for f___________ sugar during alcohol production and making bread. Enzymes found in the bacteria lactose bacillus are used to produce lactic acid from milk lactose. This is the first step in the production of cheese and dairy yoghurts. Other enzymes are found in modern biological w_________ powders that digest stains on clothing. These modern washing powders work at relatively low temperatures (<40oC) and are energy efficient because you don’t need to use high water temperatures. What temperature would be best to produce cheese from milk ?

Biological enzymes as catalysts:

Yeast is used during bread making. The carbon dioxide gas produced during the respiration of wheat sugars and carbohydrates cause the bread dough to rise. This gives the bread its light texture.

All biological washing powders contain enzymes that help with the removal of food stains. These enzymes digest and breakdown the stains at very low temperatures... below 40oC.

Yeast is an essential bacteria containing enzymes used to ferment sugar from grape, fruit or wheat into alcohol. Fermentation of sugar must be done in an oxygen free environment.

Notes

Diagram

Bread manufactureWashing powdersAlcoholWord bank: fermenting washing


Once proteins, lipids and carbohydrates are broken down into amino acids, sugars, fatty acids and glycerol, absorption into the blood stream takes place in the small intestine. The small intestine is well designed for absorption of n___________ into the blood stream. It has a thin lining, large s_________ area and a good blood supply. The surface area of the small intestine is about 10 metres squared. To achieve this huge surface area, the small intestine has a folded lining, is very long and contains millions of tiny microscopic villi. These are finger like projections which increase the surface area and help nutrient absorption into the blood.

Absorption across the villi into the blood stream:

Absorption of nutrients by the Absorption of nutrients by the villivilli

Amino acids

Fatty acids

Glucose

glycerol

Vein

Artery

Lymph vessel

Word bank: nutrients surface

There are many millions of villi found on the surface of the small intestine. They have thin walls and have a very rich blood supply. Amino acids and glucose are absorbed into the blood. Fatty acids and glycerol are absorbed into the lacteal, which then drains into the lymph system.

Notes

Diagram

Features of the small intestine villi (Villi (x 10,000 Magnification))Small intestine

Breakdown of foods along the digestive tubeScie

Breakdown of foods along the digestive tubence Interactive LTD Copyright 2005

The digestive system is simply a long tube where large nutrient molecules are converted to small molecules. In the small intestine, nutrients like g_________ and amino acids are absorbed across the villi into the hepatic artery. Here they travel to the liver and are either used immediately, stored or assimilated into your cells. Look at the overview of digestion and find out where protein, carbohydrate and lipid digestion occurs ?

Overview of digestion:Digestive system

Word bank: glucose proteins water

OesophagusStomach

Small intestine Large intestine Rectum Anus

Blood cellsAmino acids

StoolW_______ ?

WasteLipids

Fatty acids and glycerolCarbohydrate

G________ ?P_______ ?

Hepatic artery

to the liver

Key

After the digestion of proteins, carbohydrates and lipids by the digestive system, g_________ and amino acids are absorbed across the villi into the hepatic artery. Here they travel to the liver and are either used immediately, stored or assimilated into your cells. Glucose is either respired or stored in muscle and liver as glycogen. Amino acids are used to build p______ like enzymes. Excess amino acids are broken down by the liver to form urea. Fatty acids and glycerol, which are absorbed into the lymph system are used to make cell membranes, some hormones or are stored under the skin. What two hormones control the amount of glucose in your blood stream ?

Nutrient assimilation:

Assimilation of nutrientsAssimilation of nutrients

C6H12O6

6O2 6CO2

6H2O

Cells

Mitochondria Energy

C6H12O6

6O2 6CO2

6H2O

Cells

Mitochondria Energy

Digestive system

Liver

Small intestine

Blood stream

Fat

Muscle

Assimilation

Respiration

Fatty acids

Glucose

& glycerol

Aminoacids

Glucose Amino acids Fatty acids

Nutrient use


Word bank: glucose proteins


Getting the balance wrongGetting the balance wrong oneone

A healthy balanced diet should provide you with the right amount of chemical energy, vitamins and minerals. It should also be relatively low in f___ and protein (adult) and high in carbohydrates. Eating too much fatty or sugary foods, low in vitamins and minerals for long periods of time may lead to health problems later on in life. D______, atherosclerosis, obesity and heart disease are all associated with eating a poor diet. It is estimated that obesity will be the number one killer in the next twenty years in Britain.

Consuming the wrong foods: Word bank: fats diabetes

Fast Food Sweets and chocolates

With an ever increasing choice of cheap fatty fast foods, children are now more overweight and less fit when compared to children of the seventies. Obesity, diabetes and in some cases heart disease are now no longer diseases of the old. Children need to avoid ‘junk food’ and eat a more balanced diet containing the right quantities of all of the seven food groups.

Notes

Diagram

Pizza Chips


C6H12O6

6O2 6CO2

6H2O

Mitochondria Energy

Respiration

Obesity

Assimilation


Dietary intake in excess of

10,500 kJ/day (adult male)

All the chemical energy, vitamins and minerals that we require are provided by a healthy balanced diet. Overeating or under eating, eating too little vitamins and minerals can cause many health problems in adults and children. It is estimated that one in four adults will be clinically obese by 2010.

Notes

Diagram

Dietary intake in excess of daily requirements

Your brain regulates your appetite and signals when you are h______. Your body is able to regulate the amount of chemical energy that you take over many years. Consuming foods high in sugar and fat and low in bulk tend to upset the right balance. Excess chemical energy in your diet leads to greater assimilation, weight gain and eventually obesity. Some individuals who are grossly obese, store upwards of a million additional kilojoules in their body as f___. What health consequences does obesity in humans cause ?

Over consumption of nutrients:

Getting the balance wrongGetting the balance wrong twotwo

Word bank: hungry fat

C6H12O6

6O2 6CO2

6H2O

Mitochondria Energy

Respiration

Malnutrition


Dietary intake below

10,500 kJ/day (adult male) Assimilation

Poverty, drought, disease and war can lead to the failure of crops and livestock. In severe cases of famine, for example the famine in Ethiopia in 1984, millions of people may starve to death. The very old and y_______ are particularly vulnerable. Malnutrition can lead to low body weight, weak immune systems and poor development in children. Famine and malnutrition is still widespread in Africa. Live 8 is now putting pressure on the eight richest countries (G8) to reduce Africa’s debt burden. This should reduce the level of poverty and starvation in Africa.

Under consumption of nutrients:

Getting the balance wrongGetting the balance wrong threethreeScience Interactive LTD Copyright 2005

Word bank: young

Malnutrition in Africa and other developing countries is common place where daily income is less than one pound a day. Many children have less food than they require to live. It is estimated that every three seconds someone dies because of starvation.

Notes

Diagram

Dietary intake below daily requirements

Malnutrition

Healthy growth and development over your lifetime requires sensible eating and a balanced diet.

Respiration

AssimilationDietary intake at 9,750 kJ/day

Over the last 200 years, here in Western Europe our life expectancy has increased partly due to our healthy diets. Eating a low fat, medium protein, high fibre and carbohydrate diet containing lots of minerals, v________, fresh fruit and vegetables is important so that we maintain our correct b_____ weight. In schools, less junk food and more freshly prepared meals are now being offered to pupils, due to parental pressure and Jamie Oliver, the famous chef who has begun to campaign for better school diners.

Good lifelong eating habits:

Getting the balance rightGetting the balance right oneoneScience Interactive LTD Copyright 2005

Word bank: body weight

A balanced diet is important for our long life expectancy. Overeating or under eating, eating too little vitamins and minerals can cause many health problems in adults and children. In order to reach your old age, eat a healthy balanced diet...its that simple !

Notes

Diagram

Dietary intake in excess of daily requirements


Getting the balance rightGetting the balance right twotwo

Our dietary intake of foods like p________, carbohydrates and lipids should provide us with the correct amount of chemical energy to maintain our daily activities, growth (if we are children) and repair. An adult male requires about 10,500 kJ per day, equivalent to about 100 joules per second. This is the same energy that a 100 watt light bulb uses. Also research shows, that eating five portions of f____ and vegetables a day reduces the risk of developing heart disease, colon cancer and obesity. How can you get children to eat more fruit and vegetables ?

Healthy diets: Word bank: proteins fruit

Fresh fruit Cereals

Eating sufficient quantities of fresh fruit and vegetables helps us avoid many of the lifestyle diseases like obesity, cancer and diabetes. It is recommended that we all eat at least five portions of fruit and vegetables every single day. Fruit and vegetables are an excellent source of all the minerals and vitamins that we require like vitamin C. This helps us to avoid deficiency diseases like scurvy.

Notes

Diagram

Steamed potatoes Carrots


Extension questions and homework1: Define the following terms: Physical digestion, Chemical digestion, Enzymes, Excretion, Nutrients, Minerals,

Vitamins, Fibre, Absorption, Assimilation & Catalyst.

2: Look at the diagram of the three endocrine glands. Complete the table.

3: Answer the following questions:

a) The type of teeth we find in an animals mouth can tell us some information on their diet...how.

b) What is peristalsis and how does saliva help this process.

c) Acid is added to food in the stomach, what is the function of stomach acid. What is the pH of stomach acid.

d) Draw a flow chart to show what happens to food as it passes from the mouth to the anus.

e) What is the function of bile during the digestion of lipids. Where is it produced.

f) What enzyme breaks down carbohydrates to glucose. Where is this enzyme found along the gut.

g) What’s the role of the intestine’s villi and where do nutrients travel once they’ve reached the blood stream.

Healthy option

Frying

Boiling

Roasting

Rich in minerals and vitamins Cooking method

Roast potatoes Boiled potatoes Fried potatoes


4: Look at the information in the table below. Use the following table to answer questions a to d.

a) Describe any differences between males and females in children and adults.

b) What role do proteins, carbohydrates, fats, vitamin C and iron play in the human body.

c) Why does the pregnant female require huge quantities of iron and protein.

d) What would a male doing an active job require in kJ/day.


a) Most western diets contain too much fat and salt. What health problems will this cause.

b) Why is tooth enamel the hardest substance in the human body.

c) What are the four main types of teeth. Is there a relationship between the diet an animal has and the types of teeth they have.

d) Which type of teeth are not present in your milk set, but are present in your permanent set.

e) What causes tooth decay. Draw three diagram to show the main stages of tooth decay.

f) Compare the causes and effects of starvation and overeating in humans.

g) What health problems are caused by obesity in humans.

150

76

56

45

Iron (mg)

40352604514500Pregnant female

35542563912900Adult male

2039220289700Female 10 -12

20452303010800Male 10 -12

Vitamin C (mg)Fats (g)Carbohydrate (g)Protein (g)Energy (kJ)Person


6: Look at the information in the table below. Complete the table.


a) Write a paragraph to explain the action of enzymes in digestion. Include the following words: Protease, Amylase, Absorption, Proteins, Carbohydrates, Lipids, Amino-acids, Fatty-acids, Glycerol, Glucose, Blood, Capillaries and Villi.

b) What do you think is the main enzyme needed to break down the following foods: Fish, Bread, Butter, Rice, & Chicken.

Internet:Go to google.co.uk and find how glucose is used by cells during cellular respiration. Cut and paste a diagram to show how cells use sugar during cellular respiration. What are the end products and how are they excreted.

Soft bone and teethStrong teeth and bonesCalcium

Red meat and liverIron

RicketsFish oil, dairy and made by body in sunlightD

Tissue repair and immune systemC

Poor vision and skinGood eyesight and skinCarrots, milk and dairy productsA

Deficiency diseaseFunction in the bodyRich food sourcesVitamin /mineral

c) Look at the diagram of the digestive system. Match the organs to the following functions:(i) Absorbs water (ii) Contains proteases and acid (iii) Stores faeces (iv) Allows faeces to pass out of the rectum (v) Joins the throat to the stomach (vi) Most absorption of nutrients happens here (vii) Where most food molecules are broken down (viii) down by pancreatic enzymes. (ix) Stores and release bile.

science interactive ltdmrwaynescience.weebly.com/uploads/9/6/0/5/9605754/the... · 2018. 10....

Documents