1. THE NERVOUS SYSTEM
BRAIN STRUCTURE AND PHYSIOLOGY

2. TWO MAJOR DIVISIONS
• The Central Nervous System (CNS)
• Peripheral Nervous System (PNS)

3. THE CENTRAL NERVOUS SYSTEM
Controls the center of the body;
• relays messages
•processes information
•analyzes information

4. PARTS THAT MAKE UP THE CNS
• Cerebrum: largest most prominent region of the
human brain (front of the brain). Responsible for the
voluntary or conscious, activity of the body. Site of
intelligence, learning and judgment.
• Cerebellum: second largest region of the brain.
Coordinates and balances the actions of the
muscles. (back of the brain)
• Thalamus: receives messages from all the sensory
receptors throughout the body and then relays
information to the proper region of the cerebrum for
further processing.

5. THE PERIPHERAL NERVOUS SYSTEM
• Nerves stimulate regions of the head and neck,
spinal nerves, and ganglia.
• It can be divided into the sensory division and the
motor division
• Sensory division: transmits impulses from sense
organs to central nervous system.
• Motor division: transmits impulses from the central
nervous system to the muscles or glands.

6. THE NERVOUS SYSTEM :
COMMUNICATION
•A. Neurons = masses of nerve cells that transmit
information
1. Cell Body - contains the nucleus and two extensions
2. Dendrites – shorter, more numerous, receive
information
3. Axons – single, long “fiber” which conducts impulse
away from the cell body, sends information

7. BASIC DIVISIONS OF THE NERVOUS
SYSTEM

8. CARDIOVASCULAR SYSTEM

9. HUMAN CIRCULATORY SYSTEM
• Systemic Circulation –
delivers blood to all
body cells and carries
away waste
• Pulmonary
Circulation –
eliminates carbon
dioxide and
oxygenates blood
(lung pathway)

10. STRUCTURE OF THE HEART
• Heart Size: (size of a
fist) approximately 14
cm x 9 cm
• Located in the
mediastinum (space
between lungs,
backbone, sternum),
between the 2nd rib
and the 5th
intercostal space.
• The distal end of the
heart is called the
apex

11. WALLS OF THE HEART
• Epicardium – outer
layer, reduces
friction
• Myocardium –
middle layer, mostly
cardiac muscle
• Endocardium – thin
inner lining, within
chambers of the
heart

12. HEART CHAMBERS & VALVES
• Heart has 4 chambers:
• 2 Atria – thin upper
chambers that receive
blood returning to the
heart through veins.. Right
and Left Atrium
• 2 Ventricles – thick,
muscular lower chambers.
Receive blood from the
atria above them. Force
(pump) blood out of the
heart through arteries.
Right and left ventricle.
• Septum – separates the
right and left sides of the
heart

13. Valves of the Heart – allow one-way flow
of blood
• 4 total (2 Atrioventricular • Pulmonary Semilunar, or
Valves (AV) & 2 Semilunar just pulmonary valve.
valves) Between the left ventricle
• Left Atrioventricular valve and the aorta
– also called the bicuspid
valve or mitral valve.
Between left atrium and
ventricle
• Right Atrioventricular
valve – also called the
tricuspid valve. Between
right atrium and ventricle
• Aortic Semilunar – or just
aortic valve. Between the
left ventricle and the
aorta

14. BLOOD VESSELS
•Blood Vessels: arteries, veins, capillaries
•ARTERIES : strong elastic vessels which carry blood
moving away from the heart. Smallest ones are
arterioles which connect to capillaries.
•VEINS - Thinner, less muscular vessels carrying blood
toward the heart.
•Smallest ones are called venules which connect to
capillaries. Contain valves.

15. CAPILLARIES
Penetrate nearly all
tissues. Walls are
composed of a single
layer of squamous
cells – very thin.
Critical function:
allows exchange of
materials (oxygen,
nutrients) between
blood and tissues.

16. MAJOR BLOOD VESSELS
• Aorta - Ascending Aorta, Aortic
Arch, Descending Aorta, Abdominal
Aorta. The aorta is the largest artery.
(leaves left ventricle)
• Pulmonary Trunk – splits into left and
right, both lead to the lungs (leaves
left ventricle)
• Pulmonary Veins – return blood from
the lungs to the heart (connects to
left atrium)
•
• Superior and Inferior Vena Cava –
return blood from the head and body
to the heart (connects to right atrium)

17. MALE REPRODUCTIVE SYSTEM
Major Structures: testes, vas deferens, prostate, penis

18. MALE REPRODUCTIVE SYSTEM
• Function: Produces and delivers sperm
• Parts: scrotum, seminiferous tubules, epididymis, vas
deferens, testes, urethra, penis

19. PARTS
• Scrotum: where testes • Vas deferens: the tube
remain outside the that carries sperm from
body cavity. the epididymis to the
Temperature 37°C. urethra.
• Seminiferous tubules: • Urethra: tube that
located in the testis are carries urine from the
clusters of hundreds of bladder and releases it
tiny tubules. from the body.
• Epididymis: where fully • Penis: contain a
matured sperm are tube(urethra) that
stored. leads to the outside of
• Testes: makes sperms, the body.
produces testosterone.

20. FEMALE REPRODUCTION
Main Structures
•Ovary
•Uterus
•Fallopian Tubes
•Vagina
•Cervix

21. FEMALE REPRODUCTION
• OVARY - this is where the eggs
are produced through cell
division (MEIOSIS)
• - each ovary takes turns
releasing eggs every month,
twins occur if two eggs are
released
• Ovaries secrete both estrogen
and progesterone.
• Estrogen is responsible for the
appearance of secondary sex
characteristics of females
• Progesterone regulates
menstruation

22. EMBRYO DEVELOPMENT
• An egg is usually a
few days old before
it implants in the
uterus. At this point,
it has already
divided several
times and is called
a blastula.

23. Uterus
• The uterus consists of a body
and a cervix. The cervix
protrudes into the vagina.
• The uterus maintains an
environment for accepting a
fertilized egg.
• The fertilized ovum becomes
an embryo, attaches to a wall
of the uterus, creates a
placenta, and develops into a
fetus (gestates) until childbirth.
• If no fertilized egg reaches the
uterus, the lining is shed
monthly in a process known as
menstruation

24. FEMALE REPRODUCTIVE SYSTEM
• Cervix
• Fallopian Tubes
• Vagina
• Ovary
• Uterus

25. REVIEW QUESTIONS
Questions:
2. Name the stage of development the embryo is a hollow ball of
identical cells:
3. Name the part of the female reproductive system the egg cells are
released:
3. Name the structure specialized for taking blood away from the heart:
4. Which part of the brain is responsible for the voluntary or conscious,
activity of the body?
5. List the four different lobes of the brain:
6. which structure transports deoxygenated blood back to the heart?

26. REVIEW ANSWERS
Questions:
1. Name the stage of development the embryo is a hollow ball of
identical cells:
(blastula)
2. Name the part of the female reproductive system the egg cells are
released:
(ovaries)
3. Name the structure specialized for taking blood away from the heart:
(arteries)
4. Which part of the brain is responsible for the voluntary or conscious,
activity of the body? (cerebrum)
5. List the four different lobes of the brain: (parietal lobe, occipital lobe,
frontal lobe, temporal lobe)
6. which structure transports deoxygenated blood back to the heart?
(pulmonary artery)
•