Upload
ruquan-phuah
View
218
Download
0
Embed Size (px)
Citation preview
8/12/2019 Chpt 7 Respiration
1/38
8/12/2019 Chpt 7 Respiration
2/38
RESPIRATION
TWO TYPES:
(A) External respiration
-- Breathing
(B) Internal respiration
-- Cellular respiration
8/12/2019 Chpt 7 Respiration
3/38
EXTERNAL RESPIRATION
Definition:-- The mechanical process that maintains a
continuous exchange of gases between the
respiratory surfaces of an organism and its
environment.
-- Occurs through the
RESPIRATORY STRUCTURES.
8/12/2019 Chpt 7 Respiration
4/38
INTERNAL RESPIRATION
Definition:
-- The biochemical process in which energy is made available
to all living cells.
-- Involve the oxidation of organic molecules to release the
chemical energy stored within these molecules.
Organic molecules
(Glucose, Fats, Proteins)
Chemical Energy
Adenosine Triphosphate
)
8/12/2019 Chpt 7 Respiration
5/38
CELLULAR RESPIRATION
TWO TYPES:
(A) Aerobic Respiration
(B) Anaerobic Respiration
8/12/2019 Chpt 7 Respiration
6/38
Anaerobic Respiration
Definition:
-- The process that breaks down glucose when there isvery little or no oxygen.
Anaerobes (eg. Bacteria, yeast)
Human muscles and plants can sometimescarry out anaerobic respiration.
8/12/2019 Chpt 7 Respiration
7/38
Anaerobic Respiration in Human Muscles
Prolonged physical exercises
Not enough oxygen in the muscles(Oxygen Deficiency),
incur OXYGEN DEBT.
Muscles undergoes anaerobic respiration
-- produce LACTIC ACID High concentration of lactic acid in the muscles
muscle cramps and fatigue exhaustion
Equation:Glucose Lactic acid
C6H12O6 2C3H6O3 + 2ATP
8/12/2019 Chpt 7 Respiration
8/38
(A) The fate of lactic acidAfter exercises, breathe in more oxygen, lactic acid is oxidised.
lactic acid is oxidised in the LIVER.(a) Some lactic acid is oxidised to produce energy.
Lactic acid + oxygen carbon dioxide + water + energy
(b) Remaining lactic acid is converted to GLYCOGEN and
stored in the muscle cells.
Anaerobic Respiration in Human Muscles
(B) Pay off OXYGEN DEBTwhen all the lactic acids are removed
-- by increased breathing rate after exercise
Definition of OXYGEN DEBT:
-- The amount of oxygen needed to remove
lactic acid from the muscle cells.
8/12/2019 Chpt 7 Respiration
9/38
OXYGEN DEFICIT AND OXYGEN DEBT
8/12/2019 Chpt 7 Respiration
10/38
Anaerobic Respiration in Yeast
(Fermentation)
Yeast can carry out aerobic respiration and anaerobic respirationAnaerobic respiration is catalysed by ZYMASE
Equation:
Glucose ethanol + carbon dioxide + energyC6H12O6 2C2H5OH + 2CO2 + 2ATP
zymase
Use of fermentation:
1. Wine and beer making (Ethanol).
2. Bread making
-- CO2 makes dough rise.
8/12/2019 Chpt 7 Respiration
11/38
8/12/2019 Chpt 7 Respiration
12/38
Investigating anaerobic respiration in yeast
8/12/2019 Chpt 7 Respiration
13/38
8/12/2019 Chpt 7 Respiration
14/38
The Adaptations of the Respiratory Structures of organisms
1. There are many foldings or branched tubes or
air sacs or alveoli
-- to give LARGEsurface area to volume ratio-- for efficientgases exchange
2. Cells lining the respiratory structures
-- are THIN (only ONE-CELLED THICK)
-- Allows fastergaseous exchange
3. The surfaces of gaseous exchange
are constantly MOIST
-- so the gases can dissolvein it.
4. The respiratory structuresare supplied by A NETWORK OF BLOOD CAPILLARIES
-- allow the gaseous exchange between the blood
and the surroundings
X!!! INSECTS NO!!!
8/12/2019 Chpt 7 Respiration
15/38
Surface Area to Volume RatioCubes
4cm 2cm 1cm
Surface Area(cm2)
Volume (cm3)
SA/V (cm-1)
Note:
1. The largerthe size of an organism, the_____________ the surface area to volume ratio.
2. The smallerthe size of an organism, the
_____________ the surface area to volume ratio.
96
64
192
64
384
64
1.5 : 1 3 : 1 6 : 1
smaller
bigger
8/12/2019 Chpt 7 Respiration
16/38
WHY the SA/V so important?
1. The large organism (Complex multicellular organisms)
-- has larger volume
-- the gases CANNOT diffuse across the body surface FASTenough
SO WHAT?
The large organisms need specialised respiratory structures-- to obtain enough O2and remove CO2
Organisms Insects Fish Amphibians Humans
Repiratory
structures
Tracheoles in
Trachealsystem
Filaments and
lamellaein gills
Lungs and skin Alveoli in lungs
The large organisms also uses
-- to increase the rate of gaseous exchange
-- to maintain concentration gradient
8/12/2019 Chpt 7 Respiration
17/38
The respiratory structures and breathing mechanisms
Unicellular organisms (eg. Amoeba sp.)
-- No specialised respiratory structures.
-- Only the external surface of the body
-- eg. Amoeba exchanges gases through plasma membrane
Why?
ANS.
Because the unicellular organisms are small,
they have LARGEsurface area to
volume ratioSimple diffusion of gases through the
plasma membrane is sufficient to
keep them alive.
8/12/2019 Chpt 7 Respiration
18/38
Adaptations of the respiratory surfaces of
Unicellular Organisms
1. The LARGEsurface area of volume ratio-- ensures efficientgases exchange
2. They live in ponds, lake or river
-- their plasma membrane is MOIST
-- SO, gases can dissolveand diffuse across
the plasma membrane easily
3. The plasma membrane is THIN
-- to allow RAPIDdiffusion of gases.
8/12/2019 Chpt 7 Respiration
19/38
The Respiratory Structure of Small
Multicellular Organisms
Small multicellular organisms-- eg. Nematodes () - roundworms-- eg. Flatworms ()liver fluke
NOspecialised respiratory structures.
Their bodies are flat / tubular / thin
-- for efficient gaseous exchange
i i i f
8/12/2019 Chpt 7 Respiration
20/38
The respiratory structure and breathing mechanism of
INSECTS
Insects have TRACHEAL SYSTEM . Circulatosy system is NOTinvolved in transporting gases.
Spiracle
(Chitin Rings)
Th l d i f h l
8/12/2019 Chpt 7 Respiration
21/38
The structural adaptations of tracheoles
for gaseous exchange
1. Many tracheoles
-- provides large surface area
-- for diffusion of gases.
2. The tips of tracheoles
-- (a) are thinand permeable-- for efficient gases exchange
-- (b) are filled with fluid
-- gases can dissolve in it and then diffuse
8/12/2019 Chpt 7 Respiration
22/38
The breathing mechanism of insects
Inhalation Exhalation
Spiracles Open Close
Abdominal muscles Relax Contract
Air pressure Decreases Increases
Air Drawn in Forced out
8/12/2019 Chpt 7 Respiration
23/38
MIND TEST
8/12/2019 Chpt 7 Respiration
24/38
The respiratory structures of FISH (FISH LEONG???)
gill arch
8/12/2019 Chpt 7 Respiration
25/38
Gill filaments and lamellae
8/12/2019 Chpt 7 Respiration
26/38
8/12/2019 Chpt 7 Respiration
27/38
Countercurrent exchange mechanism
8/12/2019 Chpt 7 Respiration
28/38
The Structural Adaptations of gills for gaseous exchange
1. Manyfilaments and lamellae
-- provide LARGEsurface area-- for EFFICIENTgaseous exchange
2. The mambrane of the gill filaments is THIN
-- for RAPIDdiffusion of gases
3. The filaments are supplied with BLOOD CAPILLARIES
-- for EFFICIENTgaseous exchange
4. The gill filaments are MOIST
-- because surrounded by water-- allow gases to DISSOLVEin them
The efficiency of gaseous exchange further
-- by COUNTERCURRENT EXCHANGE MECHANISM &
VENTILATION
8/12/2019 Chpt 7 Respiration
29/38
EThe Breathing Mechanism of fish
Inhalation Exhalation
Buccal cavity Buccal cavity
Closed Open
Operculum
Opercular
cavity
The Respiratory Structures of Amphibians (eg Frog)
8/12/2019 Chpt 7 Respiration
30/38
The Respiratory Structures of Amphibians (eg. Frog)
The structural adaptation of the respiratory structure of
8/12/2019 Chpt 7 Respiration
31/38
The structural adaptation of the respiratory structure of
amphibians (eg. Frogskin and lungs)
(A) Skin
1. when the frog is inactive,use skin for gaseous exchange.
2. The skin is THIN,
PERMEABLE
-- for RAPIDand
EFFICIENTgaseous exchange
3. The skin is MOIST
-- because mucus secreted by
glands
4. There is a NETWORK OF
BLOOD CAPILLARIES
-- to transport gases to all the
body cells
(B) Lungs
1. Numerous inner partitionspresent in the lungs
-- to INCREASEthe surface
area for gaseous exchange
2. The membranes of the lungs
are THINand MOIST-- allow RAPIDand
EFFICIENT
gaseous exchange
3. The lungs are supplied with a
NETWORK OF BLOOD
CAPILLARIES
-- to transport gases to all
the body cells
The Breathing Mechanism of Frog
8/12/2019 Chpt 7 Respiration
32/38
The Breathing Mechanism of Frog
The Respiratory Structures of Humans
8/12/2019 Chpt 7 Respiration
33/38
The Respiratory Structures of Humans
The Structural Adaptations of the Alveoli
8/12/2019 Chpt 7 Respiration
34/38
The Structural Adaptations of the Alveoli
for Gaseous Exchange
1. NumerousAlveoli
-- provide LARGE surface area for gaseous exchange
2. The wall of the alveolus
-- is very THIN (ONE-CELL THICK)
-- allows RAPIDand EASYdiffusion of gases
3. The INNER surface of alveolus is MOIST
-- allow gases to DISSOLVEin it
4. The alveoli are covered with
a NETWORK OF BLOOD CAPILLARIES
-- provide a LARGEsurface area to volume ratio
-- for RAPIDdiffusion of gases
-- for TRANSPORTof gases
The Breathing Mechanism of Humans
8/12/2019 Chpt 7 Respiration
35/38
The Breathing Mechanism of Humans
8/12/2019 Chpt 7 Respiration
36/38
A model of human lungs
8/12/2019 Chpt 7 Respiration
37/38
A model of human lungs
to study the breathing mechanism in humans
A model of the rib cage
8/12/2019 Chpt 7 Respiration
38/38
A model of the rib cage
to demonstrate the action of intercostal muscles