Recognise Healthy Body systems HLTAP301A

Cells and tissues Cells Basic units of life More than 200 types of cells with each having a specific purpose Structure Plasma membrane outer covering enclosing the cell helps cell keep shape selectively permeable regulates the entry and exit of substances

Inside the cell Divided into 2 compartments Nucleus Cytoplasm Resembles the inside of a raw egg Yellow yolk is the nucleus White is the cytoplasm

Cells and Tissues Nucleus Centre of cell control centre Contains DNA Most adult cells have a nucleus Mature RBC does not Cytoplasm Surrounds nucleus Semi fluid 90% water, protein, carbohydrate, fats and minerals Contains organelles

Cells and Tissues Organelles Responsible for specialised functions such as cell growth maintenance repair control

Cells and Tissues Transport Plasma membrane regulates flow in and out of cell Cells are bathed in fluid classed in two types Intracellular Extracellular This aids in the process called homeostasis

transport Diffusion is the movement of a substance from a higher concentration to a lower concentration

transport Osmosis diffusion of water through a selectively permeable membrane

Cells and Tissues Reproduction is necessary for bodily growth and repair. Called mitosis 46 chromosomes arrange into 23 pairs Cell divides pulling chromosomes in half 2 identical cells are formed each containing 46 chromosomes

disorders Atrophy- means without nourishment and is a decrease in cell size which leads to wasting of tissues and organs Dysplasia- means abnormal growth and is an alteration in cell size, this can result in cancer Hyperplasia- overgrowth and can result in increase in size of tissues and organs Necrosis- death of cells Neoplasm- abnormal new growth, also called a tumour

Cells and Tissues Tissues Made of groups of cells that are similar in appearance and function Types are Epithelial Connective Muscle nervous

Cells and Tissues Epithelial tissue Covers internal and external body surfaces Forms large, continuous sheets Helps form the skin Lines hollow organs Forms glands Protects(skin), absorbs(skin), filters(respiratory) and secretes(respiratory), transports(digestive).

Epithelial tissue Classified according to appearance Simple Stratified Squamous Columnar Cuboidal

Cells and Tissues Connective tissue Most abundant Supports and connects protects underlying structures Types Dense-tendons,ligaments Loose-adipose Cartilage Bone Blood- liquid

Cells and Tissues Muscle tissue Specialised cells that contract and relax to produce movement Types Skeletal-voluntary and attached to bones Smooth-involuntary, walls of hollow organs Cardiac-involuntary, in the heart

Cells and Tissues Nervous tissue Makes up brain, spinal cord and nerves Neurons receive and conduct impulses Neuroglia support and take care of neurons

Cells and Tissues Tissue repair Occurs as soon as injury happens In one of two ways Regeneration-cells are replaced with the same type of cell as original Fibrosis-damaged cells are replaced by scar tissue

Membranes Thin sheets of tissue that cover surfaces, line cavities and surround organs Classified as epithelial or connective Epithelial include the skin, mucous membrane and serous membrane Connective includes joint cavities, covering bones,cartilage,brain and spinal cord and muscle

Cutaneous membrane The skin Outer layer is stratified, Squamous epithelium Protects the body from invading microorganisms Prevents body from drying out Underlying layer is made of dense fibrous connective tissue Strengthens and anchors top layer

Mucous membranes Lines all body cavities that open to the exterior Includes digestive, urinary, reproductive and respiratory tracts. Contain stratified Squamous epithelium Can absorb and secrete Secretion is called mucous which helps to lubricate the membrane

Serous membranes Line frontal body cavities which are not open to exterior Secrete a thin, watery fluid that allows membranes to slide past each other without friction Simple, Squamous epithelium resting on connective tissue Line cavities and fold back onto the surface of the organs Include pleura, pericardium and peritoneum

Disorders Adhesion- abnormal joining of tissues by scar tissue Cancer- abnormal growth Collagen diseases- rheumatoid arthritis, lupus= auto immune disease Gangrene- death of soft tissues Neoplasm- adenoma, osteoma, lipoma, polyps