Topic 10

respiration
12/11/2021
Part 1
Effect of exercising

Dr. Nihal Gabr

 '

Respiration

Chemical reaction that involves break down of food mainly glucose to release energy

Aerobic respiration Anaerobic respiration

C6H12O6+6O2
7 …………6CO2
- + 6H2O I
C6H12 O6……………2
> C3H6O3
Lactic acid .

Total break down of Incomplete break down of glucose

glucose using oxygen to in absence of oxygen releasing
release energy ( release small amount of energy
Advantage : release energy in absence of oxygen
large amount of energy )
Disadvantage :
A) build up lactic acid in muscles
B) release small amount of energy
C) build up oxygen debt ( aamount of oxygen needed to break
down lactic acid )
Aerobic Anaerobic
Uses oxygen No oxygen
Total break down of glucose Incomplete break down of glucose
Produces CO2 and water Produces lactic acid
Release large amount of energy Release small amount of energy
In mitochondria In cytoplasm
Effect of exercising

At rest Breathing rate is =15 breath per min , …..heart rate = 70 bpm

During exercise During exercise ……muscles need large amount of energy over a short period of time .

A) heart …..effect of exercising in heart

Increase in CARDIAC OUTPUT
= heart rate X stroke volume

Number pf beats per min Volume of blood pumped by heart / beat.

B) breathing /ventilation :
Increase in both breathing rate and increase in depth of breathing

Number of breath per minute Volume of air entering the lungs

 8 breaths ….30 seconds 15 breaths ……30 seconds
…..breaths ….60 seconds X breaths ………60 seconds
Increase in B.R
X= 16 breath per minute
X=30 breath / min.
0.5 dm3 …..1 breath
……dm3 ……16 breaths 2 dm3 ……one breath
…..dm3 ……30 breath
Total volume of air entering lungs in 1
Depth 60dm3 of air entering lungs in one minute
min 8 dm3 /minute
Explain the changes taking place DURING exercise on heart and breathing ?
During exercise creat a
problem ..anaerobic ..la
Heart : increase in both heart rate and stroke volume
ctic acid + oxygen debt
Breathing : increase in both breathing rate and depth of breathing
Solve issue …after
exercise
During exercise muscles need more energy for more contraction
P H.R and B.R
Aerobic respiration :
Glucose + oxygen…………Co2 + water + ( energy)
1. To increase blood supply to muscles
2. To supply muscles with MORE oxygen and glucose
3. For MORE aerobic respiration
4. To release MORE energy
5. For MORE muscle contraction
6. Rapid removal of large amount of Co2
7. Rapid removal of excess heat .

During exercise After exercising h.R and

Yet, insufficient supply of oxygen
1. Heart rate increase
2. Breathing rate increase and depth of breathing increase …so muscles respire
r B.r remains high then
decrease gradually
More aerobic respiration …to release energy for more
muscle contraction .
anaerobically ..producing lactic Lactic acid …liver to be
acid broken down .
Anaerobic Explain why the heart rate and breathing rate remains high AFTER exercise?

During exercise ……there was insufficient supply of oxygen , despite the increase i heart rate and
breathing rate , so muscles respired anaerobically to meet the high energy demand
Glucose ………lactic acid + ( energy )
Producing lactic acid in muscles and building oxygen debt

Breathing rate remain high

Heart rate remains high
To provide enough oxygen to pay off
For rapid removal of lactic acid from muscles
the oxygen debt
To DIFFUSE into BLOOD
Needed to break down lactic acid
To be transported to the liver
produced from anaerobic respiration
To be broken down by using oxygen debt into
CO2 and water
 What stimulates the increase in heart rate and breathing rate DURING exercise
How the increase in heart rate and breathing rate is coordinated during exercise?

Increase in supply of

Muscle ( need high O2 , glucose

demand of energy ) Increase rate of CO2 concentrationT

respiration Acid
Decrease in blood pH

A) B) Stimulate diaphargm

p
and intercostal
Cause the pace maker Brain
muscles to contract
to increase H.R more frequently

During exercise , increase in energy demand by muscles

So rate of aerobic respiration increase Send signals to Chemoreceptors that
Thus increasing CO2 concentration detect the change in
Weak acid ..that lowers the blood pH blood pH
Detected by chemoreceptors in brain
Brain send more frequent impulses to pace maker to increase heart rate
Brain send more frequent impulses to intercostal muscles and diaphragm to
stimulate them to contract more frequently ..increasing breathing rate
16/12/2021
Part 2
Gas exchange
 What stimulates the increase in heart rate and breathing rate DURING exercise
How the increase in heart rate and breathing rate during exercise is coordinated
W
During exercise , increase in energy demand by muscles PH , receptors

So rate of aerobic respiration increase impulses,

Bruin
Thus increase in carbon dioxide production . <
.

Weak acid
That lowers the blood pH
Detected by chemoreceptors in the brain
Send more frequent impulses to the pace maker to Increase heart rate
And more frequent impulses sent to the diaphragm and intercostal muscles stimulating them
to contract more frequently ... increasing breathing rate.

What stimulates the heart rate and breathing rate to stay high AFTER exercise

During exercise , increase in energy demand by muscles

And in sufficient supply of oxygen to MUSCLES , SO MUSCLES RESPIRED ANAEROBICALLY
Thus producing lactic acid
Which is an acid
That lowers the blood pH
Detected by chemoreceptors in the brain
Send more frequent impulses to the pace maker to Keep heart rate high heart rate
And more frequent impulses sent to the diaphragm and intercostal muscles stimulating them to contract more frequently ... keeping
breathing rate high.
 Gas exchange system

Adaptation
1. Lined with ciliated
epithelial cells and goblet
cells
☐ Goblet secrete mucus
which traps dust and
bacteria
Cilia beats to sweep /
move mucus out of lungs
✗
2. Rings of cartilage to
✗
keep the trachea open and
prevent it from collapse to
allow continuous air flow
into the lungs .
Alveoli adaptation
1. Many alveoli

For larger surface area , so more molecules can diffuse at the

same time , for faster gas exchange .

2. Thin wall/ wall is one cell thick

As well as the walls of capillaries.
For shorter diffusion distance , for faster gas exchange

3. Well ventilated together with continuous blood flow in

capillaries surrounding alveoli ……..to help maintain the steep
concentration gradient ..for faster gas exchange by diffusion

4. Surrounded by many blood capillaries:

To carry gas to and from the cells

5. Moist lining ;
To help dissolve the gases and prevent the dryness of alveolar
wall .
 Breathing ……muscular movement to keep the respiratory surface supplied with oxygen

Inhale Exhale

Contract Relax
External intercostal muscles

Relax Contract
Internal intercostal muscles

Rib cage Up and outwards Down and inwards

Diaphragm Contract and flatten Relax and moves upwards.

Volume of chest cavity Decrease

Increase

Pressure of air in lungs

Decrease Increase

Direction of air movement

Into lungs Air is forced out of the lungs
Un reactive
 Anaerobic respiration in yeast Industrial use of yeast

C6H12O6………..2CO2 + 2C2H5OH ( ethanol)

og
Bread
making
Wine Beer
Source of Source of
glucose is glucose is
grapes barely seed

grip
"
Respirometer
Measure the rate of respiration ..by measuring distance travelled
by oil droplet in unite time

Woodlice respire ……..O2 + glucose …….Co2 +water

Absorbed by soda lime

I

Absorb CO2. Volume of air inside the jar will decrease

Pressure of air in jar will decrease ..move droplet towards the left /maggots
Why add soda lime
1. To absorb CO2 ..to change the volume of air inside the
flask ..to observe change
2. To avoid killing of insects by excess CO2 so ethically it
should be removed
%)
°

Spirometer Measure rate of breathing , depth of breathing go.INi.ro

jm
Check list :
1. Describe the changes that happen in heart and breathing during exercise •

Heart → THR and stroke volume .

Breathing → TB.ru depth .

2. Explain the increase of heart rate and breathing rate during exercise
mm
ew
more & aerobic Respiration
glucose+ oxygen → Coat Hut CE)
more more d more
rapid removed
my
3. Explain why the heart rate and breathing rate remains high AFTER exercise?
u -

da . aerobic Resp .

lactic acid
glucose →
.

Build oxygen debt .

insufficient
HR remain high
supply during
. - - - -
-
exercise .

BR -

repay oxygen debt .

4. Explain increase in lactic avid

$ concentration during exercise?

Despite T HR and B.R

during exercise
Yet insufficient supply of oxygen to Muscles .

that can't meet Tin

energy demand
so muscles respired anaerobically
lactic acid
producing .

5. How increase in heart rate and breathing rate is coordinates

d. →
PH trot Blood
receptors Brain .
6. Labelling to the gas exchange system ( respiratory tract)
A) larynx, trachea , bronchi, bronchioles, alveoli, intercostal muscles, diaphragm

7. How trachea is adapted to carry its function

Rings of cartilage
Epithelial cells

8. Adaptation of alveoli
Many alveoli to provide large surface area
mm

Thin wall
=
Moisture
Well ventilated
-

Surrounded by blood capillaries

- -

9. Breathing definition’
10. Mechanism of inhale and exhale →

11. Composition of air. → Coz Oz Nz Temp moisture content .

12. Balanced chemical equation of anaerobic respiration in yeast ( fermintation)

Used
→
in
Brewing Cakohol )
Bread making ( CQ)
making wine (alcohol) .
13. Spirometer …used in measuring breathing rate and depth
14. Respirometer …..explain what happens .

Respire …..absorb O2 and release CO2…volume of air in jar remain the same …but in presence of soda
lime CO2 will be absorbed …so volume of air in jar will DECREASE ….pressure in jar will decrease …..oil
droplet move towards the left .
 Biology 0610 Paper 4 Respiration
Page 5 October/nov 2017 Syllabus-0610 Paper 42
11

Avoid contamination/ transmission of pathogen

Reducing / preventing transmission and spread of dusease.

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Dr.Nihal Gabr
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 Biology 0610 Paper 4 Respiration

Before exercise the lactic acid concentration was found at a constant low level
As the body was at rest carrying mostly aerobic respiration .’
Followed by a steep increase in lactic acid concentration till it peaks 17.5 min
reaching to 13.2 mmol /dm3.
Data →
quote
As there was high energy demand yet insufficient supply of oxygen to muscles
So muscles respired anaerobically
Producing lactic acid

r
providing / releasing energy needed for muscle contraction

ab
Lactic acid concentration decreases steeply followed by slower/ gradual
decrease lG
As lactic acid diffuse from muscles to blood
To be transported to liver
Where its broken down by oxygen debt into carbon dioxide and water/ converted
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to glucose
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Dr

Dr.Nihal Gabr
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Biology 0610 Paper 4 Respiration

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10

P has greater fitness

May be of different age/ gender

Dr.Nihal Gabr
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 Biology 0610 Paper 4 Respiration

① Due to increase in energy demand

① So an increase in amount of oxygen is needed
① For more aerobic respiration
① So more carbon dioxide produced
① Which is acidic ,...thus lower to the blood pH
Detected by chemoreceptors
Which send impulses to the brain that in turn send impulses to the
intercostal muscles and diaphragm ‘to contract more frequently

r
Breathing rate increase

ab
Breathing depth increase

lG
Page 9 October/november2013 Syllabus-0610 Paper 33
12
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 Biology 0610 Paper 4 Respiration

14 Page 4 May/june 2018 Syllabus-0610 Paper 41

GHEE +602 → Cocoa G tho

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Biology 0610 Paper 4 Respiration

XUE
5022g Noo -

?#
150

r
① During exercise , there was high energy demand

ab
① And though there was an increase in heart rate and breathing rate , yet there
was still insufficient supply of oxygen to muscles

①
lG
① Do muscles respired anaerobically
Producing lactic acid
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① Heart rate remains high

① Breathing rate remains high
Dr

① Repay the oxygen debt by providing sufficient amount of oxygen

① Lactic acid diffuse into blood
① To be transported to liver
① To be broken down .

Dr.Nihal Gabr
357
 Biology 0610 Paper 4 Respiration

15 Page 4 May/june 2018 Syllabus-0610 Paper 43

Constant variable

Ppm = parts per million

50/120 = 0.42 ppm/s

Dr.Nihal Gabr
406
Biology 0610 Paper 4 Respiration

State ; to allow oxygen to enter the chamber

And remove the CO2
Explain : to prevent death of crickets , as this is ethically not accepted
For crickets to respire aerobically ,

Cricket respire so release heat energy

CO2 is a green house gas leading to green house effect
Small closed jar
Cricket are moving …

Dr.Nihal Gabr
407
 Biology 0610 Paper 4 Respiration

Valid comparison

onechanyubk
a- Variable
Temp Mass .

-
- / others
g
of Resp aekept
rate .

constant
⑤

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ab
15×10-3cm
}
b- I

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①As body mass increase, the rate of oxygen consumption increaseIfor
All temperatures.)
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① Evidence : at temperature 17C [ constant temp]

When body mass was30 mg ,the rate of oxygen consumption was 7
Dr

mm

✗(10-3cm3h-1) then when mass increased to 80 gm , the ratemm

increased to 15✗(10-3cm3h-1)
① As temperature increase , the rate increase /
,

① Evidence :at constant body mass 30 gm

jur
0

At temp 17C the rate was 7 (10-3cm3h-1)

As temperature increased to 27C the rate increased to 15✗(10-3cm3h-1)
0

Dr.Nihal Gabr
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 Biology 0610 Paper 4 Respiration

2 Page 5 May/june 2011 Syllabus-0610 Paper 33

Maintain constant body temperature

Active transport
Nerve impulse transmission .
Mitosis / muscle contraction

Aerobic respiration

During exercise there was insufficient supply of oxygen to

muscles …despite the increase in H.R and b.R
So the muscles respired anaerobically
Producing lactic and building oxygen debt
So heart rate remains high to remove the lactic acid from
muscles into the blood to be delivered to liver to be broken
down using oxygen debt into CO2 and water .

Dr.Nihal Gabr
380
Biology 0610 Paper 4 Respiration

During exercise there was insufficient supply of oxygen to

muscles …despite the increase in H.R and b.R
So the muscles respired anaerobically
Producing lactic and building oxygen debt
So heart rate remains high to remove the lactic acid from muscles
into the blood to be delivered to liver to be broken down using
oxygen debt into CO2 and water .

Dr.Nihal Gabr
390
 Biology 0610 Paper 4 Respiration

9 Page 7 October/november2010 Syllabus-0610 Paper 32

Breathing rate = 11 breaths/ min

Total volume of air entering lungs in one minute
=11X 0.5 = 5.5 dm3/ min
0.5 dm3

18 breaths / min
Volume /breath
=2 dm3
Total volume =
2 x 18 = 36
dm3 / min

Dr.Nihal Gabr
391
Biology 0610 Paper 4 Respiration

Increase in both breathing rate and breathing depth

As there is an increase in energy demand by muscles
So supply the muscles with more oxygen
For more aerobic respiration
To release more energy
Fo more muscle contraction
Rapid removal of CO2

Dr.Nihal Gabr
392