protection Flashcards
list some of the structure found in the epidermis layer
Keratinocyte, Granstein cell, lagerhans cells, melanocyte.
What are the functions of the skin
Protection, sensory receptore, storage, VD3 production, thermoregulation, communication
describe in the dermis layer and things in it
soft tissue made from fat, collagen, blood vessels, gland, pili and nerve fibers, it is split into reticular (denser with thick collagen) and papilary layer (loose connective and empty space).
describe the hypodermis layer and thins in it
connective tissue from fat, thicker in areas with skin folds. the fat type depends on the species
list the 3 layers of the skin
spidermis, dermis, hypodermis
list the five layer of the skin
Basla layer (stratum basale)
Prickle -cell (stratum spicosum)
Granular (stratum Granulosum)
Clear (Stratum lucidum)
Horny/ cornified (stratum corneum)
what are melanocytes and describe their function
meanocytes produce melanin, this is stimulated by melanin stimulating hormone (anterior pituitary) and UV exposure which absorbed VD3 (this is taken to the kidney and transformed into calcitroid).
meanocytes darken the skin
describe the structure of a hair follicle
the hair shaft is made from - Medulla (inside) cortex (middle) and cutlice (outside) which is singl celled. thr root of each hair anchors the hair follicle. the deepes part of the hair follicle has a bulb which is mitoticly active, this is surronded by the root sheath.
Each hair has a pilioerector muscle whihc connect the bottom of the hair to the top and movea it.
describe the types of hair
Guard hair: stiff and on the top coat of all domestic animals (except sheep)
Tactile hair: innervated hairs which aid in sensory information
Wool: Crumpled and lack medulla, these are finner and wavy, they form the undercoat and winter coat if needed. Sheep only have this kind of hair.
what is piloerection and how does it happen
Pilli erection - hairsstand.
This means that insulation increases and can make animals look larger (cat). This also compresses the sebaceous gland. This gland secretes oil sebum which coats the skin in a thin lubricant with made from fat, this means the body hold a waterproof quality which aids in temperature regulation.
Name the two main types of skin glands and their functions
sebaceous - eptied whien the pilioerector muscle is contracted, it secreats and oil wich coat the hair finle, proving a waterproof layer.
sweat - secretes sweat (dilute) to decrease body tempreture via evaporation. (apocrine and accrine)
Name the two main types of sweat glands and their diffrences
Apocrine - secretes into the hiar, producing an odour
Eccrine - releases diluted water into exposed skin to decrease body tempreture.
List the common cornified epidermal structures found in animals.
hoof, beak, horn, claw, shell, scales.
List the major functions of the immune system
pathogen resistance
RBC removal and tissue removal
ID and removal of foreing / mutant cells
inappropriate reaction (allergies ect.)
Identify the organs and tissues of the immune system
spleen, liver, skin, thymus, lymp nodes, tonsils, adenoids and peyers patches (small intestine surface)
Describe the major differences between the innate and acquired (or adaptive) immune systems
innate - we are bone with, skin, inheritade resistance, ect.
Acuired - develped through exposure, memory T cells, ect.
what is the first line of defence and describe its function
The barrier acts to prevent entry of pathogens. It is covered in glands that secrete peptides which hold antimicrobial properties to prevent growth.
describe how inflamatation occurs
Break in the skin introduces bacteria, in response macrophages engulf pathogens and secrete cytokine and chemotaxis (this causes fever). The mast cells are active which release histamines. The cytokines cause blood vessels to dilate and this increases blood flow to the area as well and expands the capillary pores so the cytokines can enter the vessel. (cytokines cause monocytes and neutrophils to attach to blood vessels) (chemotaxis attracts neutrophils and monocytes). The monocytes produce macrophages and they help the neutrophils engulf pathogens.
what function does inflamatation serve
kills bacteria through the use of macrophages and neutrophils, the high blood pressure is from the disposal of waste and toxins
what is interferon
ubstance that is released from a cell when infected with a virus, the substance triggers the killer cells to produce enzymes capable of blocking the virus from replicating and inhibits the virus growth in the cell.
what is the complement system and describe its key traits
sequentail activation of 9 peptide which form an attack membrane that kills pathogen via lysis. it is triggered by carbohydrate chain/ pathogen antibodies destection
what are the two types of defence on the third line
antibody-mediated/humoral immunity.
Cell-mediated immunity.
what cell is involved in cell mediated immunity
T lymphocytes destroy viruses and invaded cells/ cancer cells
what cell is involved in humoral/ antibody mediates immunity
B lymphocytes activate plasma cells to secrete antibodies into the blood as immunoglobulins
Explain B lympocyctes and how they work
Antibodies are made from two chains in a Y formation. When the antigen attaches to the B cell it will respond based on its subclass:
Neutralisation, complement, phagocytes, agglutination, NK cell stimulation
list some of the antibody subclasses
IgM - Sits on the B cell receptors.
IgG - (most common) opsonin to enhance phagocytosis
IgE - Protection against worms and allergies (histamine secretion)
IgA - In secretions of the digestive, respiratory, genitourinary tracts
IgD - On the surface of many cells
Describe the difference between active & passive immunity, and the 3 ways immunity can be generated.
Active: the production of antibodies from the exposure to an antigen. (vaccinations, ect.)
- Vaccination, Live vaccination, Inactivated (killed) vaccination
Passive: transfer of preformed antibodies from one animal to another (IgG are inherited from mother to child)
- Natural exposure to a pathogen, Vaccination, Inheritance from generations
what is autoimmune disease
The body fails to identify the self from pathogens, this results in the body attacking its own cells.
explain how t lymphocyctes work
bound to the plasa memebrane of cells they have a binding site, with alfa and beta chains. the antigen bind to the T cell and forms immune synapes when the cytotoxic T cell bind to the antigen. Cytotoxic T cells release chemicals that destroy the cell before the virus can replicate inside the cell.
how is autoimmune disease caused
Exposure during injury.
Antigen modification by chemicals, viruses or mutation.
T cell exposure to foreign antigen which is similar to itself.
what are the two type of T lymphocytes
Class one is on the surface and responds to viral and cancer cells.
Class two are on the surface of dendritic cells, macrophages and B cells.
list animals and the fat colour in their hypodermis
hore -yellow
pig - grey/white
cow - white
young - brown
Respiratory barriers first line of defence consist of:
Cilia cells which reject microbes (coughing)
Nasal hairs are sensory and react to stimuli (sneezing)
Lymphoid tonsils (swell and filter lymph)
GI tract barriers first line of defence consist of:
Lymphoid tissue
Acid
pH
saliva
Genitourinary tracts barriers first line of defence consist of:
Acid, mucous
