Organ System, cavities, and homeostasis

Question 1

What is the Integumentary system? Name organs and structures. Additionaly, name its function.

Answer 1

Major organs and structures include: Skin, hair, sweat glands, and nails

1. Protection against environment
2. Temperature regulation
3. Contains many sensory structures (which
   are components of the nervous system)

Question 2

What is the Nervous system? Name organs and structures. Additionaly, provide its function.

Answer 2

Major organs and structures include: brain, spinal cord, peripheral nerves, and sensory organs and structures.

1. Short-term responses to stimuli
2. Coordinates activities of organ systems via electrical signals
3. Interprets sensory information and provides motor responses

Question 3

What is the Muscular system? Name organs and structures. Additionaly, provide its function.

Answer 3

Major organs and structures include: skeletal muscles and associated tendons

1. Movement and locomotion
2. Protection and support
3. Heat generation to maintain body temperature

Question 4

What is the skeletal system? Name organs and structures. Additionaly, provide its function.

Answer 4

Major organs and structures include: bones, bone marrow, cartilage, ligaments, and joint capsules.

1. Support and protection
2. Stores calcium and other minerals
3. Forms blood cells (red and white)

Question 5

What is the endocrine system? Name organs and structures. Additionaly, provide its function.

Answer 5

Major organs include: pituitary, thyroid, parathyroid, adrenal glands, thymus, pineal gland, and gonads.

1. Long-term responses to stimuli
2. Coordinates activities of organ systems via hormones
3. Adjusts metabolism and controls changes during growth and development

Question 6

What is the circulatory system? Name organs and structures. Additionaly, provide its function.

Answer 6

Major organs and structures include: heart, blood, and blood vessels.

1. Distributes blood cells, water,
   dissolved nutrients, gases, and
   wastes
2. Distributes heat and assists in body temperature control

Question 7

What is the Lymphatic system? Name organs and structures. Additionaly, provide its function.

Answer 7

Major organs and structures include: spleen, thymus, lymph nodules (tonsils), lymph nodes, and lymphatic vessels.

1. Defends against microbes and
   pathogens by monitoring fluids
2. Returns fluids from tissues to the bloodstream

Question 8

What is the respiratory system? Name organs and structures. Additionaly, provide its function.

Answer 8

Major organs and structures include: nasal cavities, sinuses, larynx, trachea, and lungs.

1. Deliver air to alveoli
2. Provides O2
   to blood
3. Removes CO2
   from blood
4. Sound production

Question 9

What is the digestive system? Name organs and structures. Additionaly, provide its function.

Answer 9

Major organs and structures include: mouth, pharynx, esophagus, stomach, small and large intestines, liver, gallbladder, pancreas.

Functions:
1. Processes and digests food
2. Absorbs and conserves water
3. Absorbs nutrients, eliminates waste
4. Stores energy reserves

Question 10

What is the urinary system? Name organs and structures. Additionaly, provide its function.

Answer 10

Major organs and structures include: kidneys, ureters, urinary bladder, urethra.

Functions:
1. Nitrogenous waste removal
2. Regulates urine production and water balance
3. Stores urine
4. Regulates blood ions and pH

Question 11

What is the reproductive system (female)? Name organs and structures. Additionaly, provide its function.

Answer 11

Major organs and structures include: ovaries, uterine tubes, uterus, vagina, labia, clitoris, mammary glands.

Functions:
1. Produces oocytes/hormones
2. Supports embryo development
3. Provides milk
4. Sexual intercourse

Question 12

What is the reproductive system (male)? Name organs and structures. Additionaly, provide its function.

Answer 12

Major organs and structures include: testes, seminal vesicles, epididymis, vas deferens, prostate gland, penis, scrotum.

Functions:
1. Produces sperm/hormones
2. Produces suspending fluids for sperm
3. Sexual intercourse

Question 13

What are markings used for?

Answer 13

Markings are used to describe aches, pains, and injuries. The
abdominopelvic quadrants intersect at the umbilicus (navel).

Question 14

What are regions used for?

Answer 14

Regions describe the locations of internal organs. There are
9 abdominopelvic regions:

Middle column (top to bottom): epigastric, umbilical,
hypogastric
Left and right columns (top to bottom): hypochondriac,
lumbar, inguinal

Question 15

What are the anatomical directions used for? and name them.

Answer 15

Directions help medical personnel describe superficial and deep areas of the body:

Anterior/Posterior = Ventral/Dorsal

Left/Right

Proximal/Distal

Cephalic/Caudal = Superior/Inferior

Lateral/Medial

Superficial/Deep

Question 16

What are the anatomical sections used for and name them?

Answer 16

Understanding the relationship between the internal organs requires visual cues of the human body from different perspectives.

These perspectives can be called sections ; there are three types:

Frontal plane/coronal plane

Sagittal plane

Transverse plane/cross-section

Question 17

What are the 3 true body cavities? Additionally, what are there functions?

Answer 17

1. Thoracic
2. Abdominal
3. Pelvic

They protect organs from physical trauma. What are the functions of these cavities?
They permit changes in size and shape of organs without disrupting other organs, as surfaces are composed of serous membranes.

Question 18

What does the serous membranes of the body cavities do? Additionaly, name both of them and there function.

Answer 18

The serous fluid reduces friction between surfaces moving against each other to reduce abrasion. We categorize and label serous membranes according to their position:

Parietal serous membranes cover the external wall of the cavity.
Visceral serous membrane cover the outer wall of organs, i.e. the internal wall of the cavity.

Question 19

What is the thoracic cavity?

Answer 19

Contains three separate cavities: one pericardial cavity and two pleural cavities.

1. Pericardial cavity : visceral and parietal
   pericardia surround the heart.
2. Pleural cavity : visceral and parietal pleura surround each of the lungs separately.

The mediastinum is a band of connective tissue at the top of heart that anchors arteries and veins, the trachea, esophagus, and thymus in place

Question 20

What is the Abdominal cavity?

Answer 20

Abdominal cavity contains the peritoneal cavity:

The parietal peritoneum covers abdominal wall, while the visceral peritoneum covers visceral organs.

What are the viscera?
They’re the organs in this cavity, like the liver, stomach, small intestine, spleen, part of large intestine (all connected to the mesentery).

Question 21

What is the Pelvic cavity?

Answer 21

Pelvic cavity lies inferior to the abdominal cavity:

The parietal peritoneum covers the pelvic walls but not the pelvic floor, while the visceral
peritoneum covers visceral organs in this cavity.

The viscera include the bladder, reproductive organs, rectum, and sigmoidal portion of large
intestine.

Question 22

What is homeostasis? what needs to be maintained? What are ideal values for these variables?

Answer 22

The maintenance of a relatively stable internal environment (an internal balance).

Variables , like body temp, blood pressure, pH, oxygen and carbon dioxide levels, osmotic pressure,
solute concentrations.

What needs to be maintained?
They are ranges called set points . Movement away from these causes the body to respond.

Question 23

Why is it a problem if homeostasis is disturbed? and how do you reastablish it?

Answer 23

If your variables are too far from their set point for too long,
this can be dangerous. How does the body return the internal
environment to the set point if homeostasis is disrupted?

Reestablishing homeostasis requires three elements:
1. Sensory receptor : senses the change, or the stimulus. Different stimuli need separate receptors: light, temperature, pressure, sound, taste, smell, blood gas levels, metabolite levels, etc.

2. Control/integration centre : analyzes and interprets the sensory information from the receptor and generates a response.
3. Motor effector : executes the response to the stimulus (performs an action) restoring homeostasis.

Question 24

Feedback loops; which direction must homeostasis be corrected?

Answer 24

1. NEGATIVE feedback: response moves the body AWAY
   from the stimulus (most common)
2. POSITIVE feedback: response moves the body INTO the
   stimulus (much less common)

Question 25

What is a negative feedback? and how does it do it?

Answer 25

This is an automatic
correction to variables
outside their set points.

When the body perceives cold temperatures, the body acts to
conserve body heat, minimize heat loss, increase heat production.

How does it do this?
Shivering (muscle contraction)
Divert blood flow to internal organs Decrease sweating
Goosebumps (a vestigial reaction)

Question 26

What is a positive feedback? and how does it do it? Provide an example.

Answer 26

Reinforces the stimulus; as in the body’s response is to exaggerate the stimulus or move into it.

This is used when the body must undergo a stressful/dangerous process that needs to be over
quickly. This type of response is not common and acts only in the SHORT TERM.

Examples of positive feedback: blood clotting
The body acts fast to prevent blood loss. How does it do this?
- Platelets (in the blood) aggregate due to a chemical signal CASCADE.
- Each platelet recruits more platelets and lasts ONLY so long as the wound is open.
- Then it stops.

Question 27

What is dynamic equilibrium? What happens if you fail in maintining homeostasis? What is Pathophysiology

Answer 27

always changing but remaining in balance.

Disease or illness is the result of a FAILURE of homeostasis i.e. the
body is NOT able to restore dynamic equilibrium.

As we go through the systems of the body, think about what each does, why it’s a problem if it goes wrong, and how homeostasis has failed in a given illness.