INSTITUT PENDIDIKAN GURU MALAYSIA KAMPUS SULTAN MIZAN,
22200 BESUT,
TERENGGANU DARUL IMAN
PPISMP
SEMESTER 2
BIOLOGY 1
GASEOUS EXCHANGE IN HUMAN AND PLANT
AND
THE CIRCULATORY SYSTEM
NAMAE : SITI QURRATUL AINI ULFA BINTI RODIN JAYA
I/C NO : 910606-03-6028
UNIT : 2 PPISMP SCIENCE
SUBJECT : SCIENCE (BIOLOGY 1)
CODE : SN2311P5
LECTURER’S NAME : MR. RASHID BIN MOHAMAD
SUBMISSION DATE : MARCH 2010
VOW PAGE
I admit that this coursework is my own work that I have done it myself except for the
article and summary that I have explained the sources.
Signature : (_______________________)
Name : SITI QURRATUL AINI ULFA BINTI RODIN JAYA
I/C NO : 910606-03-6028
Date : ___ ________________ 2010.
BIOLOGY 1
GASEOUS EXCHANGE IN HUMAN AND PLANT
AND
THE CIRCULATORY SYSTEM
SCIENCE DEPARTMENT
IPG KAMPUS SULTAN MIZAN, KOTA PUTRA, BESUT, TERENGGANU
APPRECIATION
Assalamualaikum.
Firstly I am very grateful because finally I did finished my coursework task on the
right time given. First of all, I would like to convey my appreciation to my parents. This is
because they had given me a lot of supports in doing this coursework perfectly.
I would like to thank my dedicated lecturer and also my coordinator from the
bottom of my heart. She have helped me and my classmates on how to understand this
coursework and make it easier and simple. Without her help, I does not sure whether I
can finished this coursework on time or not.
I also wanted to convey my appreciation to all of my friends for giving me
lots of moral supports and pulling me up each time I fall. They have helps me in doing
this coursework and they also did gave comments on my coursework such as their
opinion about the arrangement of the tasks, views about the task and so on.
Thank you.
CONTENTS
VOW PAGE I
HEADING ENCLOSURE II
CONTENTS III
INTRODUCTION 1
1.0 GRAPHIC NOTES
1.1 Gaseous Exchange in Human 2 - 9
1.2 Gaseous Exchange in Plants 10 - 15
2.0 INVESTIGATION 16 - 18
REFLECTION 19
BIBLIOGRAPHY 20
COLLABORATION FORM 21
INTRODUCTION
Living organisms need energy for cellular activities. Cells that carry out aerobic
respiration require a continuous supply of oxygen and need to remove carbon dioxide.
To enable this, organisms have developed gas exchange surfaces where respiratory
gases are exchanged between living cells and the environment.
Gaseous exchange in plants occurs mainly through pores called stomata. They
are found on the epidermis of leaves and stems of flowering plants. In dicotyledonous
leaves the stomata are found mainly on the lower epidermis. Lenticels found in the bark
of stems and root hairs with thin walls and large surface area also allow gaseous
exchange to take place.
Large organisms need a transport system to supply their cells with nutrients,
oxygen and other materials and to remove waste products. The main transport system
in mammals is the circulatory system consisting of the heart and the flow of blood
through a network of blood vessels.
1.0 GRAPHIC NOTES
1.1 GASEOUS EXCHANGE IN HUMAN
Living organisms need energy for cellular activities. Cells that carry out aerobic
respiration require a continuous supply of oxygen and to remove the carbon dioxide. To
enable this, organism has developed gas exchange surfaces where respiratory gases
are exchanged between the living cells and environment. In mammals, a respiratory
system is developed and gaseous exchange takes place in the lungs.
Have a large surface area to volume ratio.Have a short distance for rapid diffusion.Passive diffusion of gases that occurs through the cell surface membrane along the diffusion gradient is sufficient for their needs.
Small unicellular organisms
E.g : MAMMALS.Larger and more complex forms.Have a smaller surface area to volume ratio.The skin is usually impermeable to gases.The central body cells are more removed from the external environment.Needs specialised organ systems, not only for respiration, but also for digestion, circulation, excretion,reproduction, nervous and endocrine functions.
Multicellular organisms
1.1.1 Gaseous exchange in humans
The respiratory surface of a human is made-up of over 700 million air sacs, called
alveoli, inside a pair of lungs. The lungs, located in the thoracic cavity are protected by
the ribcage and separated from the abdomen by the muscular diaphragm.
- The C-shaped cartilage rings of the trachea allow the continuous movement of
air through the air passage.
- Goblet cells secrete mucus to trap dust particles and microbial spores.
- The cilia on the epithelium lining the respiratory tubes move the mucus and
trapped particles to the pharynx to be swallowed or removed via the mouth.
- Oxygen in the alveolus diffuses across the thin epithelium of the alveolus and the
endothelium of the capillary into the blood.
- It the diffuses into the red blood cells.
The function of the structure of the human gas exchange system :
Nasal cavity
Filters, moistens, and warms the air.
Pharynx
Connects the nasal and oral cavities to the larynx.
Glottis
Opening to allow air into the larynx.
Larynx
Contains vocal chords for sound production.
Trachea
Allow the passage of air from trachea to bronchioles.
Bronchi
Allow the passage of air from trachea to bronchioles.
Bronchioles
Allows the passage of air to the alveoli.
Alveoli
Acts as internal gas exchange surfaces.
Movement of oxygen and carbon dioxide in and out of the respiratory system :
Oxygen rich air from
environmentNasal cavities Pharynx Trachea
Bronchi Bronchioles Alveoli
Oxygen and carbon dioxide exchange at
alveoli
Bronchioles Bronchi Trachea Pharynx
Nasal cavities
Carbon dioxide rich air
to the environment
1.1.2 Mechanisms of Ventilation.
Breathing occurs in two stages :
a) Inspiration (Inhalation) is the process in which air is actively inhaled into the
lungs.
b) Expiration (Exhalation) is the process in which air is exhaled from the lungs.
1.1.2.1 Inspiration
1.1.2.2 Expiration
Exterbal intercostal muscles contract, internal intercostal
muscles relax
Ribcage is pulled upwards and
outwards
Diaphragm muscles contract, diaphragm moves
downwards, becomes flattened
Thoracic volume increases
Air pressure in the lungs decreases to below atmospheric
pressure
Air is drawn into the lungs along a pressure gradient
Volume of the lungs increases
1.1.3 Adaptations for gaseous exchange in the lungs
Internal intercostal muscles contract,
external intercostal muscle relax
Ribcage is pulled downwards and
inwards
Diaphragm muscles relax,
diaphragm moves upwards, return to
dome shape
Thoracic volume decreases
Air pressure in the lungs increases to higher than that of
atmosphere
Air is moved out of the lungs along the pressure gradient
Volume of the lungs decreases
Alveoli
Large surface area
moist surface
Permeable wallsSurrounded by
numerous blood capillaries
Thin walls
1.2 GASEOUS EXCHANGE IN GREEN PLANT
Gaseous exchange in plants occurs mainly through pores called stomata.
Air containing carbon dioxide enters the plant through these openings where it is used in photosynthesis and respiration. Oxygen produced by photosynthesis exits through these same openings. Also, water vapor is released into the atmosphere through these pores in a process called transpiration.
What is stomata?
Structure of stomata
They are found on the epidermis of leaves and stems of flowering plants.
In decotyledonous leaves, stomata are mainly found on the lower epidermis.
Lenticels found in the bark of stems.
Root hairs with thin walls and large surface area allow gaseous exchange to take place.
1.2.1 Stomatal opening and closing
Guard cells
Each consists of a stomatal pore
surrounded by two guard cells
kidney-shaped
contains chloroplasts
Has thinner outer wall, less elastic,
inner wall
Celulose microfibrils are radially
orientated in the cell wall and the guard
cells are joined at the end
The epidermal cells surrounding the guard cells
are called subsidiary cells
1.2.1.1 Stomatal opening
1.2.1.2 Stomatal closing
Stomatal opening is promoted by high light intensity and
low mesophyll CO2 level
Guard cell generated ATP by
photophosphorylation during
photosynthesis
Blue light is absorbed by BL photoreceptors
ATPs generated are hydrolysed to
provide energy to drive the photon-
pump
Cell become increasingly
negative charge
Potassium channel activated
K+ diffuse from the subsidiary cells into
the guard cells
Accumulation of K+ causes the water potential in guard
cells become negative
Guard cells turgid
Outer wall thinner and more elastic than the thicker
inner wall
Guard cells curve outwards Stomata opens
Factors which lead to stomata opening and closing.
Stomatal closure triggered by water
stress, high temperature,
increasing CO2, and low light intensity
Hormone abscisic acid (ABA) is
secreted by plant cells
ABA binds to receptors at the cell
membrane at the guard cells
Permeability of calcium channels
increased
Calcium ions enter the guard cells
The accumulation of Ca2+ inhibits the
proton pump
Potassium ions move out into the subsidiary cells
Water potential in guard cells increases
Water diffuses out to neighbouring
subsidiary cells by osmosis
Turgor pressure decreases Cells become flaccid Stoma closes
Importance of stomata
There is an endogenous rhythm (a biological clock). Stomata open during
the day and close during the night. (Though certain succulents which are
native to hot, dry conditions have a reversed rhythm to enable them to
economise on water loss.) However, stomata continue to open and close on
an approximately 24 hour clock (circadian = about a day) even when switched to
continuous light. The phase of this opening and closure can be shifted
(made to occur at other times of the day) by contol of the end of the dark period.
The water balance of a plant affects stomatal apperture. Wilting plants close their
stomata. The plant growth regulator abscisic acid (ABA) seems to act as a mediator
under these conditions. Water stress in the roots can transmit
(in xylem?) its influence to stomata in leaves by the signal of
ABA.
Low concentrations of CO2 cause stomata to open. If CO2-
free air is blown across stomata in darkness, their stomates open. High CO2 causes stomates to close.
Light causes stomates to open. The minimum light level for opening of stomates
in most plants is 1/1000 to 1/30 of full sunlight, just enough to cause some net
photosynthesis. Blue light (430-460nm) is nearly 10 times as effective as red light (630-680nm). The wavelengths that are
effective in the red part of the spectrum are the same as those that are effective in
photosynthesis ie is absorbed by chlorophyll. However, the blue light effect is
quite independent of photosynthesis. Photosynthesis will change intercellular CO2
concentrations and may have its effect through number iii) above.
2.0 Investigation about the blood circulatory system in human from the website.
Allow gaseous exchange of carbon dioxide (for photosynthesis) and oxygen (for respiration) between the plant and the surrounding
Regulate the rate of transpiration and control water loss by the plant
Pull water and mineral salts from the roots to the higher parts of the plant
a) Method :
a. Surfing the internet.
b. Find the information about blood circulatory system in human.
c. Analyze what is the importance of blood circulatory system in human.
b) Observation :
a. The importance of blood circulatory system
- To move materials throughout the body :
- Oxygen, carbon dioxide & other wastes, nutrients, hormones, and
antibodies.
- It moves oxygenated (oxygen-rich) blood to organs and body
tissues.
- It returns un-oxygenated (oxygen-poor) blood to the heart.
- carry the blood to every part of your body.
- Blood moves oxygen and nutrients to cells.
- Carries carbon dioxide and other wastes away from the cells.
- Sometimes the blood carries substances made in one part of the
body to another part of the body where they are needed.
c) Graphics :
A - Heart.
A heart is an organ made of cardiac muscle tissue. Heart is located behind the
breastbone, called sternum, and between the lungs. It has four compartments called
chambers. This chambers is divided by two which is the two upper chambers are called
the right and left atria. While, the two lower chambers are called the right and left
ventricles. During one heartbeat, both atriums contract at the same time. Then, both
ventricles contract at the same time. A one-way valve separates each atrium from the
ventricle below it. The blood flows only in one direction from an atrium to a ventricle,
then form a ventricle into a blood vessel. A wall prevents blood from flowing between
the two atriums or the two ventricles. This walls keeps blood rich in oxygen separate
from blood low in oxygen. If oxygen-rich blood and oxygen-poor blood were to mix, the
body cells would not get all the oxygen they need.
B Trace the pathway of blood from heart to lungs and back
A Blood, high in carbon dioxide and low in oxygen, returns from the body to the
heart. It enters the right atrium through the superior and inferior vena cava.
B The right atrium contracts, forcing the blood into the right ventricle. When the
right ventricle contracts, the blood leave the heart and goes through the
pulmonary artery to the lungs. The pulmonary arteries are the only arteries that
carry blood that is high in carbon dioxide.
C Oxygen-rich blood travels from the lungs through the pulmonary vein and into the
left atrium. The pulmonary veins are the only veins that carry oxygen-rich blood.
D The left atrium contracts and forces the blood into the left ventricle. The left
ventricle contracts, forcing the blood out of the heart and into the aorta.
REFLECTION
Assalamualaikum.
Finally, I did manage to finish this biology coursework within the time given.
Behind the process of finishing this coursework, I have gone through many difficulties
instead of finishing this coursework. I am having problems with the time management,
the sources for finding the information of the coursework, and the arrangement of the
coursework.
Time management is really testing me to be a good time manager from now until
the future. With lots of coursework, I need to find sometimes for finishing this
coursework. I tried to manage my time instead of busy finishing all the coursework
given to me. I make the schedule and follow the schedule according which coursework
should be done first and which coursework should be submit first. This is because I do
not want to keep rushing on something because sometimes when we keep rushing, our
work will end in trouble.
Besides, I really find it difficult to find the information to put in this coursework. I
went to library and borrowed some books, searched on health books at home, and
surfing the internet for various information to be taken. But, it seems like the information
is still not much. But, I tried to collect all the information and make it into group to see
which parts is still not enough for doing the coursework.
Lastly, the arrangement of the coursework sometimes is confusing me. All
contents looks the same and my head stuck in the middle of the arrangement. But,I tried
to calm myself and do it slowly. Moreover, I ask my friends help on their opinions about
the arrangement for the coursework. Finally, I did manage to finish it.
Thank you.
BIBLIOGRAPHY
B.S.Beckett, (1986) Biology A Modern Introduction GSCE Edition, Great Britain, Oxfor
University
Gairdner B.Moment, Ph.d, Helen M. Ph.d, (1977) Mainstream of Biology, USA, The
William & Wilking Company
Joan E.Rahn, (1974) Biology The science Of Life, United States Of America, Macmillan
Publishing
Lee ching (2009), Pre-U Text Stpm Biology Volume 1, Shah Alam, Selangor Darul
Ehsan, Longman
Thomas A.Steyaert, (1971) Life Are Patterns Of Order, USA, Mc Graw-Hill
www.bisnet.or.id.GASEOUSEXCHANGE , accessed on 10 March 2010
www.rsc.org/education/teachers/learnnet/cfb/CIRCULATORY.htm, accessed on 13
March 2010
www.tutorvista.com, accessed on 14 March 2010