RESPIRATION 1 ENERGY It is important to understand that the biological meaning of ‘Respiration’ refers to a chemical process taking place in all living cells. The function of this chemical process is to make energy available for all the cell’s activities which keep it alive. ‘Breathing’, in some cases, plays a part but ‘respiration’ to a biologist does not mean the same as ‘breathing’.

The petrol provides the energy that the car needs to move. Cars use petrol as fuel. It comes to a stop if we do not put petrol in the fuel tank. The petrol provides the energy that the car needs to move.

Similarly, all living organisms require energy if they are to move and carry out the complex processes of living (this energy is obtained from food)

THE CONCEPT OF ‘RESPIRATION’ IS CENTRAL TO ALL LIVING PROCESSES Respiration is a process which involves a large no of chemical reactions that help break down the nutrient molecules such as glucose in living cells to release energy.

WHAT IS THE DIFFERENCE BETWEEN BREATING AND RESPIRATION?

Breathing is only a part of the respiration process. It refers to the intake of air (Taking in Oxygen) and the letting out of air (Carbon dioxide) from our body.

One of the energy-producing reactions is called respiration 7 One of the energy-producing reactions is called respiration (Respiration is not the same thing as breathing) The chemical reactions of respiration take place in all living cells The reaction takes place between oxygen and a substance which contains carbon. The reaction produces carbon dioxide and water, and releases energy The word ‘respiration’ is used in everyday language to mean breathing; as in,for example, ‘respiration rate’ (breathing rate) or ‘artificial respiration’. In biology, it is best to avoid confusion by using the term ‘respiration’ for the chemical reaction in cells. ‘Artificial respiration’, is better described as ‘resuscitation’.

o C 4 an atom of carbon c plus a molecule of oxygen O2 combine to form a molecule of carbon dioxide CO2

One example of respiration in ourselves 15 One example of respiration in ourselves 2. The lungs absorb oxygen from the air 1. Air taken in 1.Food taken in 2.The stomach and intestine digest food. One of the products is glucose 3.The blood stream carries glucose and oxygen to the muscles The water produced as a waste product of respiration is picked up by the blood stream and may be lost in sweat, water vapour from the lungs or in urine Glucose and oxygen react to produce energy for muscle contraction 4 RESPIRATION 5 Carbon dioxide is carried to the lungs by the blood

The carbon-containing substances come from FOOD 8 The carbon-containing substances come from FOOD The oxygen comes from the AIR (or water) The energy is used to drive other chemical reactions taking place in cells One example of this is the release of energy in muscle cells to make them contract and produce movement Organisms living in water absorb oxygen from it. But it is not the O of H2O that they use. The oxygen which they can use is dissolved in the water and comes, originally, from the air.

An examples of an Energy producing reaction in living organisms: C6H12O6 + 6O2 6CO2 + 6H2O + energy sugar (glucose) oxygen carbon dioxide water

Energy use in muscle contraction 11 shoulder blade The blood stream brings food and oxygen to the muscle cells. Respiration occurs in the cells and releases energy which…… upper arm bone The drawing represents the human arm bones with two of the muscles which produce movement (biceps and triceps) lower arm bones

…….makes the muscle contract 12 …….makes the muscle contract and pull the lower arm up

CAN YOU THINK OF MORE USES OF ENERGY ?

Four Respiration Processes 1) Breathing (ventilation): air in to and out of lungs

2) External respiration: gas exchange between lung and blood 3) Internal respiration: gas exchange between blood and tissues 4) Cellular respiration: oxygen use to produce ATP, carbon dioxide as waste

16 Question 1 What is the most important point about respiration? (a) it uses oxygen (b) It produces energy (c) It produces carbon dioxide (d) It needs food and air

17 Question 2 In which part of the human body is respiration most likely to be occurring? (a) The lungs (b) The heart (c) The muscles (d) All of these Respiration will be occurring in all parts of the human body that consists of living cells. Fingernails, toenails and hair do not contain living cells and so will not be respiring

21 Answer Correct

22 Answer Incorrect

TASK Work in groups of 4 to complete the given table. Breathing While at rest After brisk walking After running Number of breaths per minute

Answer the following question based on the Task Which activity resulted in more number of breaths per minute? (Resting, brisk walking or running?) Discuss in your groups why do you think the activity resulted in more number of breaths per minute ?

Two types of Respiration Aerobic Anaerobic

Aerobic Respiration:

Aerobic respiration is a process that requires oxygen. Oxygen helps to break down the food molecules(glucose) to give rise to carbon dioxide and water. A lot of energy is produced during aerobic respiration. During aerobic respiration only one molecule of glucose will produce about thirty-eight energy units.

How is this different from Combustion? Combustion (burning): Fuel + Oxygen  Carbon + Water + energy dioxide Aerobic Respiration: Glucose + Oxygen  Carbon + Water + energy

5 The reaction between carbon and oxygen also releases energy in the form of heat and light (flames) Living organisms get their energy from reactions like this (but not reactions which are violent enough to produce flames) Some of the energy released in living organisms always appears in the form of heat

6 CO2 oxygen energy release source of carbon source of carbon Coal and wood are the carbon sources. The carbon dioxide goes up the chimney. oxygen source of carbon source of carbon

Anaerobic Respiration 23 Anaerobic respiration is involved at some stage in the preparation of these foodstuffs

Anaerobic respiration is a term used for the respiration that occurs without the use of oxygen. It also produces energy but in very less amount and without oxygen present. During Anaerobic respiration one molecule of glucose will produce only 2 energy units.

Glucose Lactic acid + Energy Anaerobic respiration in Humans can be represented by the equation: Glucose Lactic acid + Energy

Anaerobic respiration happens in humans during rigorous exercise like push ups, sprinting, weight lifting etc. However it leads to lactic acid accumulation which results in cramps in the body. We therefore breath in a lot of oxygen to breakdown the lactic acid (that has been produced as a result of the anaerobic respiration.)

Glucose →Energy+ Ethanol + Carbon dioxide Anaerobic respiration in Microorganisms like yeast and bacteria. Glucose →Energy+ Ethanol + Carbon dioxide

Black grapes growing in a vineyard 32 Black grapes growing in a vineyard Yeasts are added to crushed grapes to produce wine.

Beer fermenting 34 Yeasts added to malted barley to produce beer.

Dough rising 36 The yeast is mixed with the dough After 1 hour in a warm place the dough has risen as a result of the carbon dioxide produced by the yeast

37 The ‘holes’ in the bread are made by the carbon dioxide bubbles. This gives the bread a ‘light’ texture

TASK: Answer the following questions: How is Respiration similar and different from combustion? 2. Draw a table differentiating between Aerobic and Anaerobic Respiration. 3. How do humans respire differently from yeasts? 4. Complete the following word equation for Anaerobic respiration in Yeasts Glucose + + Energy

Aerobic and Anaerobic Anaerobic respiration Aerobic respiration When a person is doing very fast or powerful exercise the blood cannot immediately supply enough oxygen so another sort of respiration occurs. This converts glucose into energy without the need for oxygen and is known as; anaerobic respiration. The reaction is: Glucose → Energy released (2units) + lactic acid The lactic acid builds up in the muscles. High lactic acid concentrations are painful and felt as cramp. Examples of anaerobic exercise are: Sprinting Weightlifting Push ups Pull ups Aerobic respiration uses oxygen to oxidise glucose and produce energy. The equation for the oxidation of glucose is: C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy released Glucose + Oxygen → Carbon dioxide + water + (Energy released 38units) Here are a few examples of common types of aerobic exercise: if a steady pace is maintained Swimming Cycling Rowing Jogging

THE RESPIRATORY SYSTEM:

Components of the Upper Respiratory Tract:

Upper respiratory tract function: Allows air to enter (and go out) through the nose or mouth. The nasal cilia (nose hair) in the nose, acts like a filter keeping dust and dirt away from the nasal passage. It also moistens and warms the incoming air. The air then passes into the pharynx (A funnel shaped passageway located right behind the mouth) The pharynx is part of both the digestive and respiratory system.

Air then passes into the Larynx (the voice box) where speech sounds are produced. It is the upper portion of the trachea and connects the pharynx with the trachea. When we eat, a flap -- the epiglottis -- flops down to cover the Trachea (windpipe) so that food doesn't go down the windpipe.  A clearer view of the epiglottis

http://www.youtube.com/watch?v=hc1YtXc_84A&feature=related

TASK: Draw the diagram below and label only the upper respiratory tract in your note books. Read the article (only the 1st page) and write down the functions of the upper respiratory tract. Click below for article http://kidshealth.org/parent/general/body_basics/lungs.html#

Components of the Lower Respiratory Tract

The Trachea, or windpipe, is a tube that connects the pharynx and larynx to the lungs, allowing the passage of air. C-shaped cartilaginous rings  around the trachea protect it and maintains the airway.  The trachea then divides into the right and left air tubes -Bronchi (One bronchus). The bronchi allows the movement of air in and out of the lungs.

The bronchi then branch out into smaller bronchi which braches into even smaller tubes called bronchioles The bronchioles end in tiny air sacs called the alveoli where the exchange of oxygen and carbon dioxide happens.

TASK: Complete labeling the diagram given on slide 46 (Lower respiratory tract) in your notebooks. SKIT ON ‘PATH OF OXYGEN’