Healthcare - Histology and Chain of Infection

Characteristics of living things

* Maintains homeostasis
* Ability to reproduce
* Mobility
* Internal organization of cells
* Ability to grow/adapt
* Responds to stimuli
* Interacts with environment

Cell Theory

* All living things are made up of cells
* Cells are the basic unit of life
* All cells come from pre-existing cells

Temperature in relation to homeostasis

ILCREMINDERS

I - Integumentary

L - Lymphatic

C - Circulatory

R - Respiratory

E - Endocrine

M - Muscular

I - Immune

N - Nervous

D - Digestive

E - Excretory

R - Reproductive

S - Skeletal

Functions of epithelial tissue

* Lines and covers surfaces
* Secretion (saliva, sweat, etc…)
* Absorption (digestion)
* Protects organism from pathogens, injury and fluid loss

Classifications of epithelial tissue

Simple - one layer

Stratified - multiple layers

Cuboidal - cube shape

Columnar - upright rectangle shape

Squamous - squishy and flat

Functions of connective tissue

* Protection, support, binding
* Surrounds organs
* Can vary greatly in function

What is connective tissue?

Material made up of fiber forming a framework for body tissues and organs.

Types of connective tissue

* Ligaments
* Cartilage
* Tendons
* Bones
* Adipose tissue (fat)
* Scar tissue
* Loose areolar tissue
* Blood tissue

Functions of muscle tissues

* Voluntary mobility and movement
* Contractions in digestive tract/other interal organs
* Pumping the heart

Types of muscle tissue

* Smooth muscle
* Cardiac muscle
* Skeletal muscle

Smooth muscle

* Found in inner lining of organs
* Contraction of internal organs

Cardiac muscle

Allows heart to contract and pump blood

Skeletal muscle

* Attached to bone
* Provides external movement

Sections of the nervous system

* Central Nervous System (CNS): forms the brain and spinal cord
* Peripheral Nervous System (PNS): forms the cranial and spinal nerves

Glial cells

cells that assist the neurons

Epithelial tissues contain no blood vessels, meaning they are _______________

avascular

What type of tissue is always found underneath epithelial tissue?

Connective tissue

Epithelial tissues are renewed every ___ days

27

How does epithelial tissue receive nutrients and oxygen without blood vessels?

Through a process called diffusion

Why does it take tendons/ligaments longer to heal than many bone injuries?

They have less bone supply

Functions of adipose tissue

Store energy and insulate heat

What type of CT can be found in the nose, ears and vertebral disks?

Cartilage

Muscle cells are also known as:

myocytes

Longest muscle in the body

Sartorius muscle, thin muscle located in the thigh

Smallest muscle in the body

Stapedius muscle (located between the ear and ear drum)

Biggest muscle in the body

gluteus maximus (buttocks)

Strongest muscle

Masseter or gluteus maximus

Striations

repeating units called sarcomeres

What type of muscle is attached to connective tissue?

Skeletal

Homeostasis

State of having balanced levels of internal physiological conditions

Why is it important to maintain homeostasis?

* Allows organisms to adapt to the conditions of their environment
* Regulate levels of various substances in the body

Normal body temp

36\.5 - 37.2

How does your body maintain homeostasis in relation to temperature regulation?

* Through a process of thermoregulation
* If too hot, the body begins sweating and the sweat evaporates on the skin and cools the skin/release heat from body.
* If too hot, your body induces vasodilation to increase blood flow and release heat
* If too cold, your body induces vasoconstriction to decrease blood flow and conserve heat
* If too cold, your bones vibrate and cause shivering, creating warmth through kinetic energy.

Postprandial

The period following dinner or lunch

Functions of insulin

* Allows your body to use glucose for energy
* Maintains homeostasis in blood sugar levels by signalling your body to store away excess glucose.

Functions of glucagon

* Released in response to low sugar levels
* Triggers the liver to convert stores glucose into a usable form
* Stops your liver from absorbing glucose so a reasonable level remains in your bloodstream

Type 1 diabetes

* Pancreas produces little to no insulin
* Believed to be caused by an autoimmune reaction
* You need to take insulin injections to survive

Type 2 diabetes

* Your body doesn’t properly use insulin and responds poorly to insulin
* Blood levels stay consistently high
* Preventable through lifestyle changes

Hyperventilation

* Rapid/deep breathing
* Body is inhaling oxygen at faster rates than normal
* Often occurs due to panic attacks

Symptoms of hyperventilation

* Lightheadedness
* Weakness
* Confusion
* Disruption of sleep
* Dry mouth
* Muscle spasms in extremities
* Chest pain/heart palpitations

Weight of the integumentary system

2\.7 kg

Integumentary system functions

* Waterproof
* Protects body against changes in temp
* Cushions internal organs
* Protects from UV radiation
* Initial defense against infectious organisms
* Protects from loss of water
* Processes stimuli
* Stores water, fat and vitamin D

Vasodilation

* Releases heat
* Causes redness
* Heat is evenly distributed throughout body

Vasoconstriction

* Conserves heat
* Causes blueness
* Heat travels to the core

Ways to examine the integumentary system (8 ways)

* Colour
* Temperature
* Texture
* Moisture
* Thickness
* Edema (Swelling) or Inflammation
* Mobility and Turgor
* Vascularity or Bruising

Vililigo

Chronic autoimmune disorder that causes patches of skin to lose pigmentation

Melanin

Substance in skin that causes pigmentation

Papule

Raised area of skin tissue that’s less than 1 cm in diameter

Macule

Flat and discoloured area of skin less than 1 cm

ABCDE of moles

Determine whether a mole is a melanoma

* Asymmetrical shape
* Border: irregular, fading border
* Colour: uneven colour, black and brown
* Diameter: larger than a cm
* Evolving change in size/shape/colour/height

Pallor

Unhealthy pale appearance

Erythema

Unusual reddening in patches, often because of sudden injury (dilation of capillaries)

Jaundice

Yellowing of skin/eyes, casued by liver disease, decay of RBC’s or obstruction of bile duct

Cyanosis

Skin is blue due to poor circulation/insufficient oxygen supply

Use the _____ of the hand to palpate a person’s temp

back (dorsum)

Diaphoresis

Excessive sweating

What should you assess for Moisture?

Perspiration, dryness, skin folds due to activity

Symptoms of dehydration

* Dry mouth
* Yellow/no urination
* Dizziness and confusion
* Fatigue
* Black stool

Callus

Hard, thick patches of skin as the result of a blister healing

Blister

Fluid build-up between layers of skin, caused by constant friction

Edema

a condition characterized by fluids collecting in the tissues of the body (swelling)

Edema pools the post in the __________________

feet and ankles (BECAUSE OF GRAVITY)

\

Pitting edema

When pressure is applied to a swollen area of the body it leaves a ‘pit’ that takes a while to smooth over

Turgor

Elasticity of skin

Ecchymosis

A type of bruise when blood leaks out of your blood vessels and settles within the top layer of skin

Hematoma

Pooling of blood resulting from a broken blood vessel, collection of clotted blood

Texture of hair

Feel of the hair (fine, thick, thin)

Appearance may vary but hair should be shiny

Distribution of hair

Check for hair in typical places (scalp, eyebrows, eyelashes)

Alopecia

Autoimmune disease that attacks the hair follicles and causes patches of hair to fall out, usually leads to baldness

1st degree burn

* Minor burn affecting the outermost layer of skin
* Causes redness and pain
* No blisters

2nd degree burn

* Affects both the epidermis and dermis
* Causes swelling/redness + slight whiteness
* Blisters may develop

3rd degree burn

* Reaches the fat layer of the skin
* Affected areas may be black, brown, or white
* Can destroy nerves and cause numbness

Squamous cell carcinoma

* Develops in squamous cells
* Firm red nodules, raised patch of skin
* Caused by prolonged exposure to UV rays

Basal call carcinoma

* Develops in the basal cells (the cells that produce new skin cells)
* Slightly transparent bump OR a dark-coloured lesion OR a flat scaly patch.
* Cuased by UV rays

Melanoma

* Most serious type of skin cancer
* Develops in melanocytes
* Use ABCDE’s of moles

Acne

* Inflamed and infected pores
* Pores clogged with oil, dead skin cells and bacteria

Warts

* Grainy skin growths
* Caused by a virus transmitted by touch

Eczema

Type of dermatitis (inflammation in skin)

Impetigo

Bacterial infection skin condition

Decubitus ulcers

Ulcer caused by too much prolonged pressure on a specific area of the body

Autoclave

thingie that streilizes equipment

Conjunctivitis

pink eye

5 common signs of most injections

1. Swelling
2. Redness
3. Pus (drainage)
4. Warm temp
5. Tender

Strep throat

Bacterial infection that causes your throat to be sore and scratchy

Symptoms of URI

* Cough
* Fever
* Hoarse voice
* Fatigue
* Runny nose
* Swollen lympth nodes

Symptoms of gastroenteritis (food poisoning)

* Stomach pain
* Cramping
* Fever, nausea
* Diarrhea
* Dry mouth

Infection

Result of pathogens entering the body and increasing in number, altering the functioning of normal tissues

Contagious

Having the ability to spread

Incubation period

the time it takes between the initial exposure to a disease and when symptoms appear

5 modes of transmission

* Airborne
* Vector
* Direct contact
* Sexual
* Fecal/oral

Chain of Infection

1. Infectious agent
2. Reservoir (pathogen lives and replicates: food, animals, humans, surfaces)
3. Portal of exit (how the pathogen leaves the reservoir: sneezing, coughing, breathing, open wounds, excretory system)
4. Mode of transmission
5. Portal of entry (inhalation, ingestion, absorption)
6. Susceptible host (ppl w/ autoimmune disorders, babies, elderly, specific jobs w/ more exposure)