Dr. Waqas Nawaz PMAS arid agriculture university rawalpindi

1. Submitted To: Dr.Mujeeb Ur Rehman Sohoo
Submitted By: Waqas Nawaz
11-arid-975
DVM 1ST Semester

2. “Embryology Of The Heart”
Middle Of 3rd Week Rotation Of Cardiogenic Area
18
Days
21
Days
22
Days
Fusion Of The Heart Tubes Myoepicardial Mantle
1.Myoblast
2.Mesothelial Cells
The formation of Cardiac Loop The formation of Cardiac Loop
(“bending of the heart”) (“bending of the heart at 28th day)

3. The IV foramen and AV canal 4th-5th week Partitioning of AV canal 4th-5th week
Partitioning of AV canal 4th-5th week Development of AV valves
Septum formation Partitioning of Primitive ventricles
(end of 4th week)

4. Partitioning of Atrium The Sinus Venosus
(end of 4th week)
Fate of the Sinus Venosus Fate of the Sino-atrial valves
5 weeks newborn
The Truncus Arteriosus Development of Semilunar valves
8th week

5. “Heart”
Size,Shape.Location of the heart
Approximately the size of your fist
Wt. = 250-300 grams
Location
In the mediastinum between the lungs]
Superior surface of diaphragm
⅔’s of it lies to the left of the midsternal line
Anterior to the vertebral column, posterior to
the sternum
Heart Skeleton
Consists of plate of fibrous connective tissue
between atria and ventricles
Fibrous rings around valves to support
Serves as electrical insulation between atria
and ventricles
Provides site for muscle attachment

6. Pericardial Layers of the Heart
Heart Wall
Three layers of tissue:
Epicardium: This serous membrane of smooth
outer surface of heart
Myocardium: Middle layer composed of cardiac
muscle cell and responsibility for heart
contracting
Endocardium: Smooth inner surface of heart
chambers

7. “Cardiac Muscle”
Cardiac Muscle
Elongated, branching cells containing 1-
2 centrally located nuclei
Contains actin and myosin myofilaments
Intercalated disks: Specialized cell-cell
contacts
Desmosomes hold cells together and
gap junctions allow action potentials
Electrically, cardiac muscle behaves as
single unit

8. “Arteries,Veins”
Endothelium- prevents platelet aggregation
secretes substances that control diameter of blood
vessel
Tunica media- smooth muscle and connective
tissue. Innervated by sympathetic nerves
(vasoconstriction)
Missing in smallest arteries
Tunica externa- connective tissue; is vascularized
Tunica interna-smooth continuous lining

9. Major Vessels of the Heart
Vessels returning blood to the heart
include:
Superior and inferior venae cavae
Open into the right atrium
Return deoxygenated blood from body cells
Coronary sinus
Opens into the right atrium
Returns deoxygenated blood from heart
muscle (coronary veins)
Right and left pulmonary veins
Open into the left atrium
Return oxygenated blood from lungs
Major Vessels of the Heart
Vessels conveying blood away from the heart
include:
Pulmonary trunk
Carries deoxygenated blood from right ventricle to lungs
Splits into right and left pulmonary arteries
Ascending aorta
Carries oxygenated blood away from left atrium to body
organs
Three major branches:
--Brachiocephalic
--Left common carotid,
--Left subclavian artery

10. “To A Special Teacher”
When I started a school,
This day seemed so far away,
Now it’s here & I can’t believe
That time has passed so quickly…
But through your encouragement & guidance.
I feel I’m ready for tomorrow’s challenges.
Teachers play such an important part in shaping &
guiding…
Especially teacher like you.
(Dr.Mujeeb-ur-
Rehman)
Thank you for caring so much.