1B: Histology

Question 1

What are the three main layers of the heart wall?

Answer 1

Epicardium, Myocardium, Endocardium

The heart wall consists of these three layers, each with distinct structures and functions.

Question 2

What type of muscle is found in the heart?

Answer 2

Cardiac muscle

Cardiac muscle is specialized for the continuous contraction required for heart function.

Question 3

What are the components of the heart wall?

Answer 3

Epicardium, Myocardium, Endocardium, Purkinje fibers

Each component plays a critical role in heart function and structure.

Question 4

What is the function of Purkinje fibers?

Answer 4

Conduct electrical impulses in the heart

Purkinje fibers help coordinate the contraction of the heart muscle.

Question 5

What are the types of blood vessels?

Answer 5

Arteries, Capillaries, Veins

Each type of blood vessel has unique structures and functions in the circulatory system.

Question 6

What types of arteries are there?

Answer 6

Elastic arteries, Muscular arteries, Arterioles

These arteries vary in size and function, with elastic arteries accommodating high pressure.

Question 7

List the types of capillaries.

Answer 7

Continuous, Fenestrated, Sinusoidal

Each type of capillary varies in permeability and location within the body.

Question 8

What is the primary function of veins?

Answer 8

To return blood to the heart

Veins have valves to prevent backflow and ensure efficient blood return.

Question 9

What is a characteristic feature of elastic arteries?

Answer 9

High amount of elastic fibers

This allows them to stretch and recoil with each heartbeat.

Question 10

What structure is prominent in muscular arteries?

Answer 10

Internal Elastic Lamina (IEL)

IEL is a key feature that distinguishes muscular arteries from elastic arteries.

Question 11

What happens to blood flow when arteriolar sphincters are closed?

Answer 11

Arteriole - Metarteriole - thoroughfare channel - post capillary venule

This sequence allows for controlled blood flow in the microvasculature.

Question 12

What is the structure of veins compared to arteries?

Answer 12

Veins have thinner walls and irregular lumen

This structural difference is important for their function in blood return.

Question 13

What are varicose veins?

Answer 13

Condition caused by malfunction of valves in veins

This leads to blood pooling and vein enlargement.

Question 14

What is the role of vasa vasorum?

Answer 14

Supply nutrients/oxygen to medium and large blood vessels

Vasa vasorum are crucial for the health of larger vessels.

Question 15

What type of cells are associated with capillaries?

Answer 15

Endothelial cells and pericytes

Pericytes can differentiate into smooth muscle or fibroblasts during healing.

Question 16

What is edema?

Answer 16

Accumulation of interstitial fluid due to lymph vessel obstruction

This condition can result from inflammation or infections.

Question 17

True or False: The heart has a three-layered wall.

Answer 17

True

The three layers are Epicardium, Myocardium, and Endocardium.

Question 18

Fill in the blank: The basic structure of blood vessels includes TI, TM, and _______.

Answer 18

TA

These layers represent the tunica intima, tunica media, and tunica adventitia.

Question 19

What type of capillary has gaps in the endothelial layer?

Answer 19

Fenestrated capillary

These are found in areas requiring rapid exchange, like the kidneys.

Question 20

What is the function of the lymph vascular system?

Answer 20

Circulates fluid in interstitial spaces

It plays a key role in immune response and fluid balance.

Question 21

What is the primary function of the respiratory epithelium?

Answer 21

To warm, humidify, and filter the inspired air

It has blood vessels, secretes mucus, and secretes serum.

Question 22

What type of epithelium is found in the respiratory system?

Answer 22

Pseudostratified columnar ciliated epithelium with numerous goblet cells

This structure is essential for trapping particles and humidifying air.

Question 23

Where is the respiratory epithelium located?

Answer 23

Roof of nasal cavity, upper part of nasal septum, and superior turbinate

These areas are critical for the respiratory function.

Question 24

What are the components of the olfactory epithelium?

Answer 24

Olfactory cells, supporting cells, and basal cells

The olfactory epithelium is pseudostratified and specialized for smell.

Question 25

What is the function of olfactory cells?

Answer 25

They are bipolar nerve cells with nonmotile olfactory cilia that function as odor receptors ## Footnote These cells are crucial for the sense of smell.

Question 26

What do Bowman’s glands secrete?

Answer 26

Thin watery secretion (serum) ## Footnote This secretion dissolves odor substances and refreshes receptors.

Question 27

What is the conducting zone of the respiratory system?

Answer 27

Airways including nasal passages, pharynx, larynx, trachea, bronchi, and terminal bronchioles ## Footnote It delivers air to the respiratory zone.

Question 28

What is the function of the respiratory zone?

Answer 28

To carry out O2 – CO2 exchange ## Footnote It includes respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.

Question 29

What are the three types of turbinates in the nasal cavity?

Answer 29

Superior turbinate, middle turbinate, inferior turbinate ## Footnote Each type is covered by different mucosal types.

Question 30

What is the structure of the larynx?

Answer 30

A hollow muscular tube with hyaline and elastic cartilages ## Footnote It plays a role in sound generation.

Question 31

What is laryngitis and its common cause?

Answer 31

Typically due to viral infection, causing edema and hoarseness ## Footnote It can lead to a complete loss of voice.

Question 32

What characterizes the trachea?

Answer 32

Incomplete rings of hyaline cartilage and a trachealis muscle ## Footnote The wall consists of C-shaped cartilage and smooth muscle.

Question 33

What type of epithelium lines the primary bronchus?

Answer 33

Respiratory epithelium with fewer goblet cells ## Footnote This epithelium is important for airway function.

Question 34

What are Clara cells and their function?

Answer 34

Non-ciliated cells that secrete a lipoprotein and act as stem cells ## Footnote They are found in the tertiary (segmental) bronchus.

Question 35

What is bronchiolitis and its common causes in children?

Answer 35

Inflammation of air passages often caused by the measles virus or adenovirus ## Footnote It can lead to mucus clogging in bronchioles.

Question 36

What is the structure of the alveolar wall?

Answer 36

Composed of pneumocyte type I and II, collagen, elastic fibers, and extensive capillary plexus ## Footnote This structure is essential for gas exchange.

Question 37

What role do pneumocyte type II cells play?

Answer 37

They produce surfactant and can differentiate into type I pneumocytes ## Footnote These cells help maintain surface tension in alveoli.

Question 38

What is the blood-air barrier?

Answer 38

The total thickness is 0.1-0.5 um, consisting of fused basement membranes of endothelial cells and pneumocyte type I ## Footnote This barrier is critical for efficient gas exchange.

Question 39

What is emphysema and its primary cause?

Answer 39

Chronic lung disease characterized by destruction of alveolar structures, primarily caused by cigarette smoking ## Footnote It leads to loss of lung elasticity.

Question 40

What is the role of the pulmonary artery in relation to the bronchial tree?

Answer 40

It always accompanies the branching pattern of the bronchial tree ## Footnote This relationship is crucial for oxygenation of blood.