BIOL121 Lecture Notes - Lecture 4: Lamina Propria, Pleural Cavity, Serous Fluid
MEMBRANES AND INTEGUMENTARY SYSTEM (SKIN)
1.42 Describe the general role of tissue membranes in the body
• The integumentary system consists of the cutaneous membrane or skin and the
accessory structures
• Ie cutaneous membrane is simply the skin
1.43 Generally identify and describe four tissue membranes found in the body:
• Ie this means that it lines the main tissues in the body
1.43.1 Mucous
• Line passageways and chambers that communicate with external environment
• Location: digestive, respiratory, reproductive and urinary tracts
• Function: Moisture important in passageways- reduce friction, assist in absorption
and secretion
• Connective tissue component (lamina propria)
1.43.2 Serous – 3 Types: pleura; peritoneum; pericardium. 2 layers: Parietal and visceral
layers.
• Location: the sealed, internal subdivisions of the body cavities (don’t communicate
with exterior)
• Function: to reduce friction between opposing surfaces- transdate fluid
• Three types:
- Pleura: lines pleural cavities and covers lungs
- Peritoneum: lines peritoneal cavity and covers the organ surfaces
- Pericardium: lines pericardial cavity and covers heart
• Build up of serous fluid causes problems within body- caused by inflammation of
membrane due to friction, infection or injury
• Friction: adhesions (fibrous connections that lock the membranes together and/or
excess fluid production)
1.43.3 Cutaneous
• Two components- epidermis and dermis
• Epidermis: superficial epithelium ie sits above the dermis
- Protects dermis
- Prevents water loss and entry of pathogens
• Dermis: underlying area of connective tissues
- Papillary layer: nourishes and supports epidermis
- Reticular layer: has sensory receptors that detect touch, pressure, pain,
vibration and temp. Blood vessels assist in temp regulation
• Accessory structures: hair, exocrine glands and nails (located primarily in dermis and
protrude through epidermis to skin surface)
- Hair follicles: hairs protect skull and provide delicate touch sensations on
general body surface
- Exocrine glands: assist in temp regulation and water excretion
- Nails: protect and support tips of fingers and toes
1.43.4 Synovial
• Location: Line the cavity of synovial joints
• Function: Produces synovial fluid which lubricates the articulating surfaces and
moves into the cartilage, providing oxygen and nutrients
1.45 Generally describe what the integumentary system is and its basic function;
protection, thermoregulation, synthesis, excretion, pigmentation, houses blood and fat
• Two major components- cutaneous membranes and accessory structures
• Account for about 16% of body weight
• Hypodermis (subcutaneous adipose layer)- separates integument from the deep
fascia and other organs
- First line of defence- prevents pathogen entry
- Informs brain about environment- via thermoreceptors (heat and cold), fine
touch receptors, pressure receptors and nociceptors (pain)
- Reduces water loss
- Protects against impact, chemicals and UV light
- Maintain body temp- through insulation or evaporative cooling
- Synthesis of vitamin D
- Production of keratin- protect against abrasion and provide water resistance
- Production of melanin (pigment)- protects underlying tissue from UV
radiation
- Storage of lipids in adipocytes in dermis and adipose layer of hypodermis
- Excretion of salts and water by sweat glands and small amounts of organic
waste by sebaceous glands
1.46 List the 2 layers of the skin and the tissues present in it
• Epidermis and dermis
• Epidermis: comprised from epithelium tissue
• Dermis: from areolar tissue and dense irregular connective tissue
1.47 Label epidermis, dermis and hypodermis layers associated with the skin on diagrams
and identify them on models
Document Summary
1. 42 describe the general role of tissue membranes in the body: the integumentary system consists of the cutaneous membrane or skin and the accessory structures. 1. 43 generally identify and describe four tissue membranes found in the body: Ie this means that it lines the main tissues in the body. Line passageways and chambers that communicate with external environment: function: moisture important in passageways- reduce friction, assist in absorption. Location: digestive, respiratory, reproductive and urinary tracts and secretion: connective tissue component (lamina propria) 1. 43. 2 serous 3 types: pleura; peritoneum; pericardium. Location: the sealed, i(cid:374)ter(cid:374)al su(cid:271)divisio(cid:374)s of the (cid:271)ody (cid:272)avities (do(cid:374)"t (cid:272)o(cid:373)(cid:373)u(cid:374)i(cid:272)ate with exterior: function: to reduce friction between opposing surfaces- transdate fluid, three types: Pleura: lines pleural cavities and covers lungs. Peritoneum: lines peritoneal cavity and covers the organ surfaces. 1. 43. 3 cutaneous: two components- epidermis and dermis, epidermis: superficial epithelium ie sits above the dermis. Prevents water loss and entry of pathogens: dermis: underlying area of connective tissues.
