The Circulatory System

2. Circulatory System
(Transport System)
Transports import gases and nutrients to body cells and carry
metabolic wastes to the organs for excretion
Plays important roles in maintaining
homeostasis by
Exchanging
molecules
Controlling the chemical
makeup of the blood
Open type Closed type (Cardiovascular
System)
Blood is
pumped
through
open-ended
vessels and
diffuses out
of the body
Blood is pumped by the
heart through vessels and
does not fill body cavities
Includes the
following
parts
Blood Heart Blood vessels

3.  Is also referred to as the transport system
 Transporting important gases and
nutrients to the cells of the body,
 Also carries metabolic wastes such as
carbon dioxide (𝐶𝑂2) and salts to the
organs of excretion which include the
lungs , kidney, and skins

4. The Circulatory System plays important roles in maintaining homeostasis
2. The circulatory system controls the
chemical makeup of the blood by
continuously transporting it through
organs such as the Liver and the kidneys.
1. The circulatory system controls the
makeup of the environment in which the
cells live by exchanging molecules

5. Two basic types of circulatory systems:
1. The open circulatory systems
 Blood is pumped through open-ended vessels and diffuses
out of the body, bathing all organs it passes through.
 There are no arteries in which increased blood pressure may
occur.
 Invertebrates: crustaceans, spiders, and grasshoppers
 Requires less energy for pumping blood.
 Suits small animals
 Animals with slow metabolism are generally less active
in processes such as locomotion, digestion, and
respiration.

6. Two basic types of circulatory systems:
2. The closed circulatory systems
 Also referred to as the cardiovascular system.
 This system consists of a heart and a network of vessels.
 Blood is confined to this network of vessels.
 Vertebrates
 Suitable for organisms with fast metabolism
 Blood is circulated at a higher pressure and delivered
quickly through out the body.

7. Heart
 A muscular organ about the size of your clenched fist.
 Drives the blood through the blood vessels.
 Located between the lungs and its tip is slightly pointed to the left of the midline of
the body.
 Contracts about 72 times per minute on average, or more than 100 000 times a day,
unceasingly in a person’s lifetime.
 Its primary responsibility is to pump oxygen-rich blood throughout the body while
carrying blood that contains metabolic waste such as carbon dioxide to the lungs.

9. Epicardium
Myocardium
Endocardium Pericardium
Structure of the Heart The heart, a hollow organ, is formed by three different layers of
cardiac muscles:
The membrane that lines the
interior of the heart.
It is made up of a thin,
smooth layer of cells that
resembles the squamous
epithelium in the walls of
the oral cavity.
The heart is Surrounded by
a fluid-filled sac
The thickest layer of the cardiac muscles.
It is responsible for pumping blood through the blood vessels.
The thin, outermost layer of
the heart wall that extends
with the fibrous sac
enclosing the heart.
Pericardium
 Consist of two membranes.
The space bet. these membranes of
the pericardium protects the heart
from friction as the heart contracts.
 Connects the heart to the
diaphragm and the
breastbone

10. Pulmonary Circuit
The right side
pumps oxygen-
poor blood to the
lungs
Systemic Circuit
The left side of the
heart received
oxygen-rich blood
from the lungs. This
blood is then
circulated to the rest
of the body.

11. Left Ventricle
 Atria - Upper Chambers
 Received blood coming into the heart and
pump it into the ventricles
 Ventricles – the heart’s two lower champers
 thicker muscular walls, pump
blood out of the heart and
into the other parts of the
body
 Atrioventricular valves
 Also known as tricuspid valve
 Entrance valve
 Located between the right atrium and the right ventricle.

12. Types of Blood Vessels
1. Arteries - carry blood away from the heart and into the capillaries that connect to the
tissues.
- Thick and elastic walls which are strong enough to receive high-pressure blood
pumped from the ventricles of the heart.
Aorta - Largest artery, it has the thickest wall.
Arterioles - The smallest subdivisions of the arteries
- Have thinner walls and less elastic connective tissues.
2. Veins - Return blood to the hear and drain the capillaries in the tissues. the
-their walls are thinner but wider than those of the arteries
Venules - Smallest veins

13. 3. Capillaries - Finest and smallest of the three types of blood vessels.
- Have much thinner and less elastic walls
- Facilitate the exchange of materials between the blood and body cells or between the
blood and the lung tissues.
- Connect arterioles and venules

14.  Helps maintain homeostasis.
 Transports oxygen and nutrients to the cells
and removes carbon dioxide, ammonia, and
other waste products
 Boost the immune system to protect a person
against disease-causing organisms.
 Helps maintain a relatively constant body temperature

15. Two main components of the blood:
plasma and formed elements
 55% of blood volume, the liquid part of
the blood, and 90% of water
The substance with the second largest
percentage in the plasma.
1. Albumin
Plasma Protein includes the ff:
– is the most abundant plasma protein in the
blood.
- Manufactured in the liver
- It is essential in maintaining the osmotic
pressure of the blood to regulate blood flow
2. Clotting factors
- Are proteins that are switched on in a
certain sequence called clotting cascade when
a blood vessel is damaged.
3.Antibodies
- In the plasma help fight infections.
 Transports food nutrients and oxygen to
the cells of the body.
 It also carries waste from the cells.

16.  Makeup about 45% of the blood volume and
consist primarily of three cellular components:
1. Red blood cells (RBCs) also called erythrocytes
2. White blood cells (WBCs) also called leukocytes
3. Platelets also called thrombocytes

17.  Makeup about 45% of the blood volume and consist primarily of three cellular
components:
1. Red blood cells (RBCs) also called erythrocytes
 Make up about 40% of the blood’s volume.
 Concave (with the central area thinner than the
edges), and disk-shaped cells.
 The ability of RBCs to carry oxygen is due to
hemoglobin
2. White blood cells (WBCs) also called leukocytes
 Round cells with prominent nuclei of varying
shapes and sizes.
 Défense against microorganisms

19. b. Eosinophils
- Bright pink, beadlike
granules.
- They kill parasites, destroy
cancer cells, and are involved
in allergic responses.
c. Basophils
- Have large, dark blue
granules, often with obscure
nuclei.
a. Neutrophils – constitute
about 60% of all leukocytes
• Lavender granules and
are active in fighting
infections through
phagocytosis - a process
that involves engulfing
and ingesting bacteria,
fungi, and other foreign
debris.

20. - Lack of visible
granules
1. Lymphocytes - the second most abundant type of white blood cells
- Both of which help protect
against viral infections and
detect and destroy some cancer
cells
a. T Lymphocytes
b. Natural Killer cells
(NK Cells)
c. B Lymphocytes - Produce antibodies

21. 2. Monocytes - Largest in size
- They function as phagocytes by ingesting
dead or damaged cells.
- Help defend the body against many infectious organisms
- Also called thrombocytes
- Smallest of the blood’s formed elements.
- Play an important role in the clotting process by clumping together to
form a plug that helps seal a blood vessel at a bleeding site.
- Release substances that help promote further clotting.
Thrombocytopenia - A condition, when the number of platelets is too low
- bruising and abnormal bleeding can occur.
Thrombocythemia - A condition when the number of platelets is too high
- The blood may clot excessively, causing a stroke or heart attack

22. Exercise 1.3
Make a chart of the components of the human blood
showing their functions and their relative
proportions in terms of blood volume.