RHS Honors A&P Unit 5 Protection

Cutaneous membrane

The skin; composed of epidermal and dermal layers

Mucous membrane

Membrane that secretes mucus that lubricates the surface of organs and keeps them moist; exposed to the exterior of the body

Serous membrane

Membrane that lines a cavity without an opening to the outside of the body

Synovial membrane

membrane lining the capsule of a joint

What are the functions of the integument system?

protecting the body from:

- fluid loss

- injury

- infection

- temperature regulation

- collecting information from the outside

Skin: Epidermis

Outer layer of skin that consists of dead cells that stop water loss and protect the body against invasion by microorganisms.

Skin: Dermis

Middle layer of skin containing sensory receptors, sweat glands, hair follicles and small blood vessels.

Skin: Hair

Flexible epithelial structures composed of keratinized cells; produced by the hair follicle.

Skin: Hair follicle

Structure of both inner and outer root sheaths that produces hair.

Skin: Sebaceous gland

Glands that excrete sebum into hair follicles

Skin: Sweat gland

The glands that secrete sweat, located in the dermal layer of the skin.

5 layers of epidermis (deep to superficial)

1. stratum basale

2. stratum spinosum

3. stratum granulosum

4. stratum lucidum

5. stratum corneum

What cells are responsible for skin color?

melanocytes

Melanin production

Stimulated by exposure to sunlight and protect cells below by absorbing and blocking UV radiation

Nails are composed of

hard, keratinized epidermal cells located over the dorsal surfaces of the ends of fingers and toes

arrector pili muscle

The small, involuntary muscle in the base of the hair follicle; causes hair to "stand up" when the muscle contracts.

Rule of Nines

a method used in calculating body surface area affected by burns

First-degree burn

Superficial burns through only the epidermis.

Second-degree burn

A burn marked by pain, blistering, and superficial destruction of dermis with edema and hyperemia of the tissues beneath the burn.

Third-degree burn

a burn involving all layers of the skin; characterized by the destruction of the epidermis and dermis, with damage or destruction of subcutaneous tissue

Fourth-degree burns

involves not only all layers of skin, but also underlying fat, muscles, bone, or internal organs.

Skin cancer

abnormal growth of skin cells

Basal cell carcinoma

Most common and least severe type of skin cancer; often characterized by light or pearly nodules.

Malignant melanoma

Most serious form of skin cancer; often characterized by black or dark brown patches on the skin that may appear uneven in texture, jagged, or raised.

ABCDE rule

asymmetry, border, color, diameter, evolving

Function of the lymphatic vessels

Collect excess tissue fluid and blood proteins

Return tissue fluid and blood proteins to bloodstream

2 structures of the lymphatic system

1. lymphatic vessels and 2. lymphoid tissues

Function of lymph

protects the body from disease

Lymph node

a small knob of tissue in the lymphatic system that filters lymph, trapping bacteria and other microorganisms that cause disease

Lymphoid organs

-Consist of lymph nodes, spleen, appendix, adenoids, thymus, tonsils, and small patches of tissue in the small intestines.

Lymph Nodes: Located at intervals through the lymph vessel system. Contains lymphocytes and plasma cells.

Spleen: Filters blood, stores of RBC and macrophages.

Thymus: Secrets hormones. Major site of lymphocyte production.

Function of tonsils

Help defend the body against infection by trapping pathogens that enter the throat.

Function of thymus

site of T cell maturation

Function of Peyer's Patches

Capture and destroy bacteria in the intestine

Function of the spleen

- forms monocytes & lymphocytes

- stores RBC & releases into circulation if needed

- filters old RBC's from blood

1st line of defense in the immune system

Physical barriers

- skin

- tears

- mucus

- saliva

- stomach acids

2nd line of defense in the immune system

Inflammation (immunity) - functions immediately as an effective barrier to microbes

Role of natural killer cells

- not phagocytes

- kill abnormal cells by secreting cytotoxic perforins and granzymes

- produce cytokines to trigger other immune cells

Describe the inflammatory response

Cells at the wound release histamines which dilate blood vessels. This brings more blood (with phagocytes) to the wound

Phagocyte function

type of white blood cell the engulfs dead cells

innate body defenses

nonspecific, general barriers; from skin to phagocytes to fever to inflammation

Role of a fever

Fever is a defense mechanism that can destroy many types of microbes.

Fever also helps fight viral infections by increasing interferon production.

While high fevers can be dangerous, some doctors recommend letting low fevers run their course without taking aspirin or ibuprofen.

Immune response

the body's specific recognition, response, and memory to a pathogen attack

Antigen

a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.

Hapten

small molecule that has to bind to a larger molecule to form an antigen

B cell

A lymphocyte that produces proteins that help destroy pathogens.

T cell

a lymphocyte that identifies pathogens and distinguishes one pathogen from another

Humoral immunity

B cells produce antibodies after exposure to specific antigens; type of adaptive immunity

Role of plasma cells

specific immunity produced by B cells that produce antibodies that circulate in body fluids

Monoclonal antibodies

a collection of identical antibodies that interact with a single antigen site

Antibodies

Specialized proteins that aid in destroying infectious agents

5 antibody classes

IgM, IgA, IgD, IgG, IgE

4 major types of transplants

Autografts, isografts, allografts, xenografts

Autografts

tissue transplanted from one site to another on the same person

Isografts

tissue grafts from an identical person (identical twin)

Allografts

grafts transplanted from individuals that are not genetically identical but belong to the same species

Xenografts

tissue taken from a different animal species

Allergies

Inappropriate or excessive immune responses to antigens

Autoimmune diseases

Diseases caused when the immune system loses tolerance for self and turns against certain molecules in the body.

Immunodeficiencies

failure of the immune system to protect the body adequately from infection, due to the absence or insufficiency of some component process or substance.