L4 - Histology Cardiovascular and Respiratory Systems

Endocardium

Inner lining of heart chambers and valves.

Myocardium

Cardiac muscle layer of the heart.

Epicardium

Outer layer of the heart, also visceral pericardium.

Intercalated Discs

Connections between cardiac muscle cells for synchronized contraction.

Purkinje Fibres

Specialized fibers for conducting impulses in the heart.

Aorta

Main artery carrying blood from the heart.

Tunica Intima

Innermost layer of blood vessel, includes endothelium.

Tunica Media

Middle layer of blood vessel, contains smooth muscle.

Tunica Externa

Outer layer of blood vessel, connective tissue sheath.

Elastic Artery

Artery with high elasticity to accommodate blood pressure.

Muscular Artery

Artery with thicker walls, less compliant than elastic arteries.

Systole

Phase of heart contraction, blood is ejected.

Diastole

Phase of heart relaxation, chambers fill with blood.

Bronchus

Main airway leading to the lungs, contains cartilage.

Bronchiole

Smaller airway in the lungs, lacks cartilage.

Ciliated Columnar Epithelium

Type of epithelium found in respiratory tract.

Pseudostratified Epithelium

Single layer of cells appearing stratified, found in trachea.

Alveoli

Tiny air sacs in lungs for gas exchange.

Alveolar Phagocytes

Immune cells in alveoli that engulf pathogens.

Smooth Muscle

Muscle type in blood vessels and bronchioles.

Submucosal Glands

Glands in the respiratory tract that secrete mucus.

Basal Lamina

Thin layer supporting epithelial cells in lungs.