chap1-transportform5-120218082802-phpapp01 (1)
-
Upload
santhiya-madhavan -
Category
Documents
-
view
225 -
download
0
Transcript of chap1-transportform5-120218082802-phpapp01 (1)
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
1/107
chapter 1 :Transport
Learning objective:1. Understanding the importance of having transport
system in some multicellular organisms
2. Synthesize the concept of the circulatory system
3. Understanding the mechanism of blood clotting
4. Synthesize the concept of the lymphatic system
5. Understanding the role of the circulatory system in thebody's defense mechanism
6. Appreciate a healthy cardiovascular system
7. Understanding the transport of substances in plants
8. Synthesize the concept of the transport of substances
in plants
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
2/107
1.1 The importance of having a transport system
in some multicellular organisms
Learning outcomes:
1. Identify the problems that could be faced by
multicellular organisms in obtaining their
cellular requirements and getting rid of waste
product
2. Suggest how these problems are overcome in
multicellular organisms
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
3/107
Transport
To describe how the substance in our body
move from one part to the other part
Transport process varies in different types of
organism
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
4/107
Difference transport in unicellular and
multicellular organisms
1. Unicellular organism
Ex?
They have large total surface area to volume
(TSA/V) ration that enable substance to diffuseeasily into the cell
To obtain oxygen and nutrients directly fromexternal environment
Carbon dioxide and other waste product alsoeliminated by diffusion through plasmamembrane
So, They do not need any internal transport
system
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
5/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
6/107
Multicellular organisms
Ex?
The TSA/V ration decreases
Cells often located away from external surface ofthe body
Diffusion rate also decrease which is a limitingfactor to cellular activities in large animals
These organism have specialized structure toincrease surface area ( alveolus)
They also need circulatory system to
Distribute nutrients and oxygen
Remove waste product
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
7/107
exercise
Examine cuboid A and B. Calculate the TSA/V
of both cuboids. Assume that the cuboids are
two organisms.
Which organisms obtain their cellular
requirement (O2 and nutrients) and removing
their waste product( co2 and urea) easily?
Why?
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
8/107
Assignments
1. Why does unicellular organisms canundergoes diffusion process to transport theirnutrients and waste products while
multicellular organisms cannot?Elaborate your answer by giving suitable
explanation.
( 8 marks)
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
9/107
1.2 The circulatory systemLearning Outcomes:
1. State what a circulatory system is2. State the three components of the circulatory system in
humans and animals
3. State the medium of transport in humans and animals
4. State the composition of human blood5. Explain the function of blood and haemolymph in transport
6. Describe the structure of human blood vessel
7. Explain how blood is propelled through human circulatory
system8. Explain briefly how blood pressure regulated
9. Compare and contrast the circulatory system in thefollowing: human, fish and amphibians
10. Conceptualise the circulatory systems in humans
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
10/107
Functions of the circulatory systemThe circulatory system has three functions:
1. Transportingsubstances around the body. These
include oxygen, glucose, carbon dioxide, nutrients,
water and waste products.
3. Protectingthe body. Blood contains cells
and anti-bodies that fight infection andclotting agents to stop bleeding.
2. Controllingbody temperature.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
11/107
3 components of circulatory system
1. Medium of transport/ Blood
2. Blood vessel
3. Heart
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
12/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
13/107
1. Medium of transport/ Blood
Animals:Blood which consist of blood plasma, blood cells
( RBC, WBC) and plateles
Invertebrates:Ex:
Use haemolymph(fluid in hoemocoel)
Hoemocoel: rongga
Functions: transport material around the body
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
14/107
Blood
Blood is the bodys means of transportingsubstances around. It transports:
oxygenfrom the lungs to the heart and then to the
bodys tissues
carbon dioxidefrom the tissues to the heart and
then to the lungs to be expired
materials like hormonesfrom one organ to another
nutrients(especially glucose) and mineralsfrom the
intestines to the tissues
waste productsto the kidneys.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
15/107
Composition of Human Blood
Blood: connective tissue that are composed of
1. Cellular components (45%)
Platelets
Erythrocytes (RBC)
Leucocytes( WBC)
1. Plasma (55%)
Water(90%)
Soluble solutes
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
16/107
Cellular components ( 45%)
1. Platelets
Fragments of cells from bone marrow
No nucleus Important for blood clotting process
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
17/107
1.Platelets
Formed in red bone marrow.
Produce thrombokinase
a chemical needed for blood clotting.
Platelets help to repair tissuesand close woundsboth
internally and externally.
When needed, they grow intoirregular shapes and stick together to
form a plugover the wound.
Plateletsare also carried in the blood.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
18/107
They aggregate and release factors which
promote the blood coagulation.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
19/107
2.Red blood cells
Also called erythrocytes.
Disc-shaped.
Made in the bone marrow.
Contain a red-coloured compound
called haemoglobinwhich bonds
with oxygen to formoxyhaemoglobin.
Transport oxygen to the tissues.
Blood is made up of a number of different elements.
The most common cell in blood is the red blood cell.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
20/107
In the other vertebrates (e.g. fishes,
amphibians, reptilians and birds), they have a
nucleus.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
21/107
3.White blood cells
Also called leucocytes.
They are bigger than red
blood cells and have large
nuclei.
Act as the bodys defencesystem.
Blood also contains white blood cells.
Some white blood cells surround and consume
harmful microbes.
Some produce chemicals called antibodiesthat
fight infection.
colorless
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
22/107
Each type of leukocyte is present in the blood
in different proportions:
neutrophil 50 - 70 %
eosinophil 2 - 4 %
basophil 0,5 - 1 %
lymphocyte 20 - 40 %
monocyte 3 - 8 %
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
23/107
In fact, these granules have a different affinity
towards neutral, acid or basic stains and give
the cytoplasm different colors.
So, granulocytes distinguish themselves in
neutrophil, eosinophil (or acidophil) and
basophil.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
24/107
Leukocytes ( WBC)
1. Granulocytes
2. A granulocytes
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
25/107
1. Granulocytes
Granular cytoplasm
filled with microscopic granules that are littlesacs containing enzymes, compounds thatdigest microorganisms.
Lobed nuclei( kelepek)
Form in bone marrow
Consist of:
1. Basophils
2. Neutrophils
3. Eosinophils
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
26/107
Neutrophils
As a Phagocytes
Which digest
bacteria and deadcells
By phagocytosis
process
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
27/107
Neutrophils
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
28/107
Eosinophils
Control allergic
responses
Kill parasitic wormsby release enzyme.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
29/107
eosinophils
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
30/107
Basophils
Secretes heparin
to prevent blood
clotting
Involve in
combating
inflammatory andallergic reactions
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
31/107
basophils
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
32/107
In the different types of granulocytes, the
granules are different and help us to
distinguish them.
In fact, these granules have a different affinity
towards neutral, acid or basic stains and give
the cytoplasm different colors.
So, granulocytes distinguish themselves in
neutrophil, eosinophil (or acidophil) and
basophil
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
33/107
2. Agranulocytes
Clear cytoplasm
Nuclei are not lobed( terkelepek)
Consist of
1. Lymphocytes
2. monocytes
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
34/107
Lymphocytesare cells which, besides being presentin the blood,
Its populate the lymphoid tissues and organs too, aswell as the lymph circulating in the lymphaticvessel.
An antibody is a molecule able to bind itself to
molecules of a complementary shapecalled antigens, and recognize them.
As for all proteins, even the antibodies are coded by
genes. On the basis of a recombination mechanism of
some of these genes, every lymphocyte producesantibodies of a specific shape.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
35/107
Lymphocytes
Produce
antibodies
Neutralize toxins Produce immune
responses against
foreign substance Largest leucocytes
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
36/107
Monocytes
Phagocytes
Engulf digested
bacteria anddead cells
Origin: frombone marrow
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
37/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
38/107
Difference between RBC
AND WBC
characteristics RBC WBC
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
39/107
1. SHAPE a) Erythrocytes are
biconcave disc serves to:
Increase surface area tovolume ratio
Increase diffusion rate of
gaseous exchange
b) No nucleus to gives space
for great quantities ofhaemoglobin
Leucocytes have nuclei
Not have haemoglobin
Larger than erythrocytesDo not have fixed shaped
2.FUNCTION Has haem group
Contains iron atom
For the site of oxygen
binding
When the partial pressure of
o2 is high,
Haemoglobin will combine
with o2 to form
OXYHAEMOGLOBIN
Responsible for the defense
of organism against disease
If pathogen invade the body,
number of leucocytes will
increase
3. DIAMETER 8 micrometer 15 micro meter
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
40/107
LIFESPAN 120 days
Destroyed by phagocytes
(WBC) in the liver and
spleen(limpa)
A few days by phagocytosis
process
MANUFACT
URED IN
Bone marrow
Rate: 2 million/ second
Bone marrow(granulocytes)
But may migrate to thymus
gland or lymph node
For their growth and
development stage
Lymphatic system (
agranucolytes)
3. DIAMETER 8 micrometer
Thickness: 2 micrometer
15 micro meter
4.Number of
bloodcell/mm3
5 million/mm3 6000-10000/mm3
(Ration: 1WBC:700RBC)
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
41/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
42/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
43/107
PLASMA
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
44/107
Plasma
90% water
inorganic salts(Na+, Mg2+, Cl-)
glucoseantibodies
urea and other waste products
plasma proteins.(ex: albumin, fibrinogen,prothrombin)
Dissolved gases( oxygen and carbon dioxide)
Hormones ( insulin)
The blood cells and platelets are suspended in a
substance called plasma. Plasma is made up of:
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
45/107
The plasma is a slightly alkaline fluid, with a
typical yellowish color
The mineral substances are dissolved in ionic
form, that is dissociated into positive and
negative ions.
Ex: Ca2+
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
46/107
Plasma can be separated from theother components of blood using
a centrifuge.
plasma
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
47/107
Functions of blood in Transport
1. Transport in oxygen
2. Transport of carbon dioxide
3. Transport of water to tissues
4. Transport of excretory waste products
5. Transport of hormones
6. Transport of heat7. Transport of absorbed food materials
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
48/107
1. Transport of oxygen
Transport o2 from lung/alveoluscells/ all
part of body
Oxygen combine with haemoglobin in
erythrocytes to form = oxyhaemoglobin
Oxyhaemoglobin dissociates into haemoglobin
and 02
O2 then supplied for cellular respiration (ATP)
Hb + O2 ---> HbO
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
49/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
50/107
2. Transport of carbon dioxide
Cellular respiration release co2
Glucose + o2 -energy +co2+ water
Carbon dioxide transported from cells to lungs/
alveolus in the form of:
a)Hydrogen carbonate ions
b) Carbaminohemoglobin
c)Dissolves directly in the blood plasma
When the blood reaches the lungs, the co2 release
and diffuse out of the blood into the alveoli
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
51/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
52/107
Hydrogen carbonate ions are produced when
carbon dioxide produced by tissue respiration
is absorbed by blood plasma.
In your lungs, hydrogen carbonate ions turn
back to carbon dioxide which is excreted when
you exhale.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
53/107
Carbaminohaemoglobin is a combination of
carbon dioxide and hemoglobin,
CO2HHb, being one of the forms in which
carbon dioxide exists in the blood.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
54/107
3. Transport of water to tissues
Water is transported by blood to provide a
medium for biochemical reactions
4 T t f t t
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
55/107
4.Transport of excretory waste
products
1. Deamination
Process removing the amino group from the
excess amino acid.
The amino group is converted to ammonia
and then to urea by the liver
From liver, urea transported by blood to
kidneys to be excreted
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
56/107
5.Transport of hormones
Blood transport hormones produced by
endocrine gland to the target organs
Ex: insulin and glucagon carried by blood from
pancreas to the liver
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
57/107
6. Transport of heat
Blood helps regulate body temperature by
distributing heat
7 Transport of absorbed food
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
58/107
7. Transport of absorbed food
materials
Soluble digested food, vitamins and mineral
absorbed into capillaries of the villi in small
intestine
Ex: simple sugar: glucose
Amino acids
Water soluble vitamins
Mineral salts
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
59/107
They are transported by the hepatic portal
veinfrom small intestine to liver and then to
the heart
Other food materials are absorbed into
lacteals in the villi
Ex: fatty acids, glycerol , vitamin ADEK (Fat
soluble susbtances)
They are then transported by the lymph into
the blood circulatory system via the left
subclavian vein
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
60/107
Hepatic portal vein
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
61/107
Lacteal and villi
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
62/107
Lacteal and villi
l h
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
63/107
lymph
S b l i i
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
64/107
Subclavian vein
Function of Haemolymph in transport
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
65/107
Function of Haemolymph in transport
Haemolymph:
the circulating fluid in open tissue spaces ofinvertebrates
A circulating blood-like nutritive fluid which
fills the entire body cavity called haemocoel A circulating system in invertebrates = open
circulatory system because the haemolymph:
1. Is not confined to vessels only2. Bathes the tissues and internal organs
directly
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
66/107
Nutrients such as digested food and hormones
diffuse from haemolymph into cells. Waste products diffuse out from cells into the
haemolymph
Haemolymph does not transport respiratorygases.
Gaseous exchange via the tracheal system
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
67/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
68/107
2. Blood vessels
Consist of arteries
Capillaries
Veins
functions: carries blood around the body
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
69/107
Structure of human
blood vessels
Blood vessels
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
70/107
Blood vesselsThere are three typesof blood vessels,
blood fromthe heart
blood to theheart
arterycarries blood
back intothe heart
carries bloodaway fromthe heart
carries blood to andfrom the bodys cells
vein
arteries capillaries Veins
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
71/107
arteries capillaries Veins
Carry oxygenated
blood away from the
heart to all parts ofthe body
Except pulmonary
artery
Sites for the
exchange of
respiratory gases,nutrients and wastes
Transport
deoxygenated blood
from all parts of thebody to the heart
except pulmonary
vein
Blood pressure:High blood pressure
in arteries
Lower than arteriesbut higher than veins
Lowerthan arteries
Thickmuscular wall
Lumen size small
One cell thickness
Lumen is very small
Thinnerwall
Lumen size is large
No valve except
aorta
No valve Valve present to
prevent backflow of
blood
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
72/107
arteries capillaries Veins
To transport blood
quickly at high
pressure from the
heart to tissues
Allow rapid gaseous
exchange between
blood and the body
cells by diffusion
Allow blood from
tissues to return to
the heart
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
73/107
The ARTERY
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
74/107
The ARTERY
thick muscle and
elastic fibres
Arteries carry oxygenated blood away from the heart.
the elastic fibres allow the
artery to stretchunder
pressure
the thick muscle cancontract to pushthe
blood along.
The VEIN
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
75/107
The VEIN
Veins carry deoxygenated blood towards from the
heart.
thin muscle and
elastic fibres
veins have valves
which act to stop the
blood from going in
the wrong direction.
body muscles surround the veins
so that when they contract to
move the body, they also
squeeze the veins and push the
blood along the vessel.
The CAPILLARY
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
76/107
The CAPILLARY
Capillaries link Arterioles with
Venus
the wall of a
capillary
is only one cell thick
they exchange materials
between the blood and
other body cells.
The exchange of materials
between the blood and thebody can only occur
through capillaries.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
77/107
Blood vessels
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
78/107
Blood vesselsthickouter wall
thickinner layer of muscle
and elastic fibres
narrowcentral tube
(lumen)
thinouter wall
thininner layer of muscle and
elastic fibres
wide central tube(lumen)
wall only one cellthick
ARTERY
VEIN CAPILLARY
Blood vessels: valves
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
79/107
Blood vessels: valves
When blood is flowing against gravity, or when a vein is
squeezed by muscle action, there is a risk that blood willflow in the wrong direction. Veinshave valvesto prevent
backflow.
blood tothe
heart
backflow
preventedvein valveopen
vein valveclosed
The valves allow
blood to flow in the
correct direction
but close if blood
starts to flow in the
wrong direction.
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
80/107
3. Heart
A heart is an organ that generates pressure to
pump the blood through out the body
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
81/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
82/107
How blood is propelled through
the human circulatory system?
Location of the Heart
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
83/107
Location of the Heart
The heart is located between the lungs behindthe sternum and above the diaphragm.
It is surrounded by the pericardium.
It is a fluid filled sac that surrounds the heart
Its size is about that of a fist, and its weight is
about 250-300 g.
Location of the heart in the thorax
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
84/107
Location of the heart in the thorax
Anatomy of the heart
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
85/107
Anatomy of the heart
Heart made up of myogenic cardiac
muscles which contract and relaxautomatically throughout life
It is not controlled by nervous system
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
86/107
The human heart has four chambers:
1. Left and right Atrium (atria= plural)
Upper chambers which receive blood
returning to the heart
Thin -walled2. Left and right ventricles
Lower chambers which pump blood out of
the heart Thick walled
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
87/107
Septum:
Separatesthe right chambers from the left
chambers
The valves: ensure that blood flows only in one
direction.
1. Tricuspid valve
2. Bicuspid valve
3. Semi lunar valve
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
88/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
89/107
The Heart Valves
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
90/107
The Heart Valves
The tricuspid valve-the valve between the
right atrium and right ventricle
The bicuspid valve- the valve between left
atrium and left ventricle
Semi lunar valve- the valves at the base ofaorta and pulmonary artery
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
91/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
92/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
93/107
The right pump forces deoxygenated blood tothe lungs
The left pump forces oxygenatedblood to
other parts of the body
Pumping of the heart/ the heartbeat
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
94/107
Pumping of the heart/ the heartbeat
http://www.pbs.org/wgbh/nova/heart/heartmap.html
How does the heart beat?
http://www.pbs.org/wgbh/nova/heart/heartmap.htmlhttp://www.pbs.org/wgbh/nova/heart/heartmap.htmlhttp://www.pbs.org/wgbh/nova/heart/heartmap.html -
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
95/107
How does the heart beat?
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
96/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
97/107
SAN and AVN
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
98/107
SAN and AVN
Electrical signal begins in the sinoatrial (SA)
node: "natural pacemaker."
causes the atria to contract.
Blood is then forced into the ventricles
The signal then passes through theatrioventricular (AV) node.
sends the signal to the ventricles via the
bundle of His causes the ventricles to contract.
And pump the blood out of the heart
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
99/107
Right ventricle pumps the blood intopulmonary arterywhich forces the blood to
the lung
Left ventricle pumps the blood into aortawhich forces the blood to all part of the body
The Conduction System
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
100/107
The Conduction System
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
101/107
Left ventricle is thickerand more muscularthan the wall of the right ventricles
Because it needs to generate greater pressure
to pump blood to all parts of the body
While the right ventricle pumps the blood to
the lungs only
What is the cardiac cycle?
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
102/107
What is the cardiac cycle?
Cardiac cycle is the series of events that occurduring one complete heartbeat
Including contraction (systole) and relaxation (
diastole) of both atria and ventricles
Th i t i l d (SAN) i iti t th
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
103/107
The sino atrial node(SAN) can initiate theheartbeat on its own
Sympathetic nerve carrying impulse to the heartcan increase the heart rate
Parasympathetic nerve can slow it down
The heart rate increase when: Increase in the secretion of hormone
(adrenaline)
An increase in partial pressure of carbondioxide in the blood
Body temperature is elevated
How does blood in the veins flow back
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
104/107
to the heart?
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
105/107
1.Muscle relaxed , valves closed
2.Muscles contract, upper valves open and
blood is forced upwards , lower valve remain
close
3. Muscles relaxed, upper valves closed, lower
valve opens as a result of muscle contraction
elsewhere and blood flows forwards
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
106/107
-
8/13/2019 chap1-transportform5-120218082802-phpapp01 (1)
107/107