Tissue structure Flashcards
Skin layers
- Epidermis
Stratified squamous keratinized cells - Dermis
Dense irregular CT (contains hair follicles, sweat glands, sebaceous glands) - contains most collagen - Hypodermis
Loose CT + adipose tissue
Epidermis structure
Stratified squamous keratinized cells
Sweat glands structure
Simple or stratified cuboidal cells
Sweat duct = stains darker
Sweat glands = stain lighter.
Endothelial cells
Type of epithelial cell that lines cavities of circulatory system i.e. blood vessels and lymphatic vessels
Proximal vs distal convoluted tubules (kidney)
Proximal :
Larger diameter, irregular lumen.
Columnar/cuboidal cells with brush border (microvilli) → appear fuzzy.
More eosinophilic (pink-stained cytoplasm) due to mitochondria.
Fewer nuclei visible as cells are larger.
Distal:
Smaller diameter, more regular round lumen.
Lack of brush border, appearing clearer.
Less eosinophilic cytoplasm.
More nuclei per section, as cells are smaller
Bile duct
Found in portal triad
Cuboidal to columnar epithelial lining
Small, round lumen compared to hepatic artery
Arteries vs Veins
Arteries:
Thicker walls due to prominent smooth muscle layers.
Smaller lumen.
Well-defined muscle layer.
Intact endothelium with clear elastic lamina.
Veins:
Thinner walls, less smooth muscle.
Larger, collapsed lumen (irregular in shape).
Valves may be visible, especially in larger veins.
Collagen fibres
Protein fibres found throughout body
Provides strength + cushioning.
5 types
Type I Collagen
Thick fibres
Most collagen
Type II Collagen
Thin fibres, cartilage
Type III collagen
Reticulin fibres
Stained with Gordans & Sweets stain (black)
Locations:
Bone marrow, spleen, lymph nodes
Stroma of liver.
Basement membranes.
In dermis + around capillaries.
Blood vessels.
Type IV Collagen
Found in basement membrane
- found in glomerulus BM (kidney)
- found in lungs (alveoli)
- found in skin.
- found in capillaries + endothelial BM (blood vessels).
Type VII Collagen
Anchors basement membrane to connective tissue
What is the outermost layer of the skin called?
Epidermis
True or False: The dermis is located beneath the epidermis.
True
What type of epithelium is the epidermis primarily composed of?
Stratified squamous epithelium
Fill in the blank: The primary cell type found in the epidermis is __________.
Keratinocyte
What is the function of melanocytes in the skin?
To produce melanin, which gives skin its color.
Which layer of the skin contains blood vessels and nerves?
Dermis
What is the main function of the renal corpuscle in the kidney?
Filtration of blood to form urine.
True or False: The nephron is the functional unit of the kidney.
True
What are the two main components of the renal corpuscle?
Glomerulus and Bowman’s capsule
What type of epithelium lines the renal tubules?
Simple cuboidal epithelium
In the liver, what is the functional unit called?
Lobule
What type of cells are primarily found in the hepatic lobules?
Hepatocytes
Fill in the blank: The liver produces __________, which is important for digestion.
Bile
What is the role of Kupffer cells in the liver?
They act as macrophages to remove pathogens and debris.
True or False: Alveoli are the sites of gas exchange in the lungs.
True
What type of epithelium is found in the alveoli?
Simple squamous epithelium
What is the function of the surfactant produced in the lungs?
To reduce surface tension and prevent alveolar collapse.
What is the primary function of the intestines?
Digestion and absorption of nutrients.
Which part of the intestine is primarily responsible for nutrient absorption?
Small intestine
What type of epithelium lines the intestines?
Simple columnar epithelium
True or False: The large intestine is mainly involved in water absorption.
True
Fill in the blank: The circular folds in the small intestine that increase surface area are called __________.
Plicae circulares
What are villi and where are they found?
Finger-like projections found in the small intestine.
What is the primary role of goblet cells in the intestines?
To secrete mucus for lubrication.
Which layer of the skin contains adipose tissue?
Hypodermis (subcutaneous layer)
What structure connects the renal pelvis to the bladder?
Ureter
Fill in the blank: The liver is located in the __________ quadrant of the abdomen.
Right upper
What is the main function of the renal tubules?
Reabsorption and secretion of substances in urine formation.
