Introduction To Physiology

Question 1

What is physiology?

Answer 1

The science of studying the functional activities and mechanisms in the biological body.

For example: why can the heart automatically beat?

Question 2

What are the Greek origins of the word physiology?

Answer 2

Derived from ‘physis’ (nature) and ‘logos’ (study).

Question 3

Who is known as the father of physiology?

Answer 3

Galen, who was the first to perform experiments to understand body functions.

Question 4

Who was the first modern physiologist?

Answer 4

William Harvey, who described the circulatory system in the 17th century.

Question 5

What concept did Claude Bernard introduce?

Answer 5

The concept of ‘milieu interieur’ or internal environment, establishing physiology as the scientific basis of medicine.

Question 6

What is the father of modern physiology known for?

Answer 6

Claude Bernard is known as the father of modern physiology.

Question 7

Name the subdivisions of physiology.

Answer 7

• Viral physiology
• Bacterial physiology
• Cellular physiology
• Plant physiology
• Human physiology

Question 8

What is human physiology?

Answer 8

The science of studying the rule of physiological functions in the human body.

Question 9

Differentiate between process and function in physiology.

Answer 9

• Process: How do we breathe?
• Function: Why do we breathe?

Question 10

What is homeostasis?

Answer 10

The existence and maintenance of a relatively constant environment within the body despite fluctuations in the external or internal environment.

Question 11

Who coined the term ‘homeostasis’?

Answer 11

Walter Cannon in 1929.

Question 12

What are the key themes in physiology?

Answer 12

• Homeostasis
• Communication and movement across cell membranes

Question 13

What does the integumentary system consist of?

Answer 13

The integument (skin) and structures derived from it (hair, nails, and oil/sweat glands).

Question 14

What are the functions of the integumentary system?

Answer 14

• Protects the body
• Regulates body temperature
• Eliminates wastes
• Receives stimuli (tactile, temperature, pain)

Question 15

What is the skeletal system composed of?

Answer 15

Bones, cartilage, and ligaments.

Question 16

What are the functions of the skeletal system?

Answer 16

• Provides body support and protection
• Permits movement and leverage
• Produces blood cells
• Stores minerals

Question 17

What is the function of the muscular system?

Answer 17

• Effects body movements
• Maintains posture
• Produces body heat

Question 18

What does the lymphatic system consist of?

Answer 18

Lymphatic vessels, lymph nodes, and other lymphatic organs.

Question 19

What are the functions of the lymphatic system?

Answer 19

• Removes foreign substances from blood and lymph
• Combats disease
• Maintains tissue fluid balance
• Absorbs dietary fats from the digestive tract

Question 20

What is the function of the respiratory system?

Answer 20

• Supplies oxygen to the blood
• Eliminates carbon dioxide
• Helps regulate acid-base balance

Question 21

What is the main function of the digestive system?

Answer 21

Mechanically and chemically breaks down foods for cellular use and eliminates undigested wastes.

Question 22

What does the nervous system consist of?

Answer 22

Brain, spinal cord, nerves, and sensory organs such as the eye and ear.

Question 23

What are the functions of the nervous system?

Answer 23

• Detects and responds to changes in the environment
• Enables reasoning and memory
• Regulates body activities

Question 24

What is the endocrine system composed of?

Answer 24

Hormone-producing glands such as the hypothalamus, pituitary gland, thyroid, adrenal glands, and others.

Question 25

What are the functions of the endocrine system?

Answer 25

Controls and integrates body functions via hormones secreted into the bloodstream.

Question 26

What is the cardiovascular system's main function?

Answer 26

* Transports respiratory gases, nutrients, and wastes * Protects against disease and fluid loss * Helps regulate body temperature and acid-base balance

Question 27

What does the urinary system do?

Answer 27

* Removes various wastes from the blood * Regulates chemical composition, volume, and electrolyte balance of the blood * Maintains acid-base balance

Question 28

What is the reproductive system's function?

Answer 28

Reproduces the organism and produces sex hormones.

Question 29

What is the average body composition percentage of protein in a young adult male?

Answer 29

18%

Question 30

What is the average body composition percentage of fat in a young adult male?

Answer 30

15%

Question 31

What is the average body composition percentage of water in a young adult male?

Answer 31

60%

Question 32

How is body fluid content divided?

Answer 32

* Extracellular fluid (ECF) * Intracellular fluid (ICF)

Question 33

What is the approximate volume of intracellular fluid (ICF) in the body?

Answer 33

About 28 liters.

Question 34

What are the cations found in extracellular fluid (ECF)?

Answer 34

* Na+ * K+ * Mg2+

Question 35

What are the anions found in extracellular fluid (ECF)?

Answer 35

* Cl- * HCO3-

Question 36

What is passive transport?

Answer 36

Movement of substances across cell membranes without using cellular energy.

Question 37

What is osmosis?

Answer 37

The movement of water across a semipermeable membrane.

Question 38

What is active transport?

Answer 38

Movement of substances across cell membranes that requires energy, typically using carrier proteins.

Question 39

What is the role of the receptor in homeostatic regulation?

Answer 39

Receives information about a change in the environment.

Question 40

What is feedback in homeostatic regulation?

Answer 40

The signal sent by the effector, which can be either negative or positive.

Question 41

True or False: Homeostasis is essential for survival.

Answer 41

True

Question 42

What are the main components of a feedback system?

Answer 42

Receptor, Control Center, Effector, Afferent Pathway, Efferent Pathway ## Footnote The feedback system processes information and responds to stimuli.

Question 43

What is feedback in a biological system?

Answer 43

The signal sent by the effector ## Footnote Feedback can either be negative or positive.

Question 44

What is negative feedback?

Answer 44

When the effector opposes the stimulus and reverses the direction of change ## Footnote Example: Decrease in blood glucose and blood pressure.

Question 45

What is positive feedback?

Answer 45

When the effector reinforces the stimulus and amplifies the direction of change ## Footnote Example: Uterine contractions during childbirth that trigger the release of oxytocin.

Question 46

Fill in the blank: Negative feedback causes the temperature to _______.

Answer 46

rise ## Footnote This occurs when the effector opposes a dropping temperature.

Question 47

What happens during positive feedback in childbirth?

Answer 47

Uterine contractions trigger the release of oxytocin, amplifying the contractions ## Footnote This leads to further release of oxytocin.

Question 48

What is an example of positive feedback in the body?

Answer 48

Blood clotting, protein digestion ## Footnote These processes involve amplifying the response to a stimulus.

Question 49

How does the body respond to heat stress?

Answer 49

Sweating and vasodilation ## Footnote Sweating cools the body through evaporation, while vasodilation increases blood flow to the skin.

Question 50

What role do thermoreceptors play in temperature regulation?

Answer 50

They detect changes in body temperature and send messages to the hypothalamus ## Footnote This initiates responses to either cool down or warm up the body.

Question 51

What is vasoconstriction?

Answer 51

Constricts smooth muscle of arterioles to limit blood flow and reduce heat loss ## Footnote This is a response to cold temperatures.

Question 52

What is piloerection?

Answer 52

Constricts smooth muscle around hair follicles, causing hair to stand on end ## Footnote Erect hair traps warm air next to the skin, helping to retain heat.

Question 53

How does shivering contribute to temperature regulation?

Answer 53

Initiates rhythmic contractions of skeletal muscles ## Footnote This generates heat to warm the body.

Question 54

Take Home Message: What are examples of negative feedback?

Answer 54

1. Decrease in blood glucose 2. Decrease in blood pressure ## Footnote These are responses that oppose changes in the body.

Question 55

Take Home Message: What are examples of positive feedback?

Answer 55

1. Clotting 2. Parturition ## Footnote These processes amplify the response to a stimulus.

Question 56

What is a compartment on it own?

Answer 56

Blood; it has plasma (ECF) and blood cells (ICF)