Please enable JavaScript.
Coggle requires JavaScript to display documents.
organisation of animal tissues - Coggle Diagram
organisation of animal tissues
smallest to largest
organelle, cell, tissue, organ, organ system, organism
tissue
= group of cells that work together to perform a specific function
4 main types in body
epithelial tissue
muscle tissue
connective tissue
nervous tissue
Epithelial tissue & cells
epithelial tissues
tissues are made up of almost entirely cells - don't contain blood vessels - cells receive nutrients by diffusion from tissue fluid in the underlying connective tissue
cells are very close together& form continuous sheets - adjacent cells are bound together by lateral contacts, such as plant cells (plasmodesmata) tight junctions & chromosomes
can have smooth surfaces or projections (either cilia - hair like structures which waft mucus etc out of the airways or the egg cell down the oviduct, or microvilli - increase SA of the cell, e.g. in small intestine for absorption of digested food)
have short cell cycles - the cells divide up 2 or 3 times a day to replace worn or damaged tissues
specialised to carry out its function of protection, absorption, filtration, excretion & secretion
a lining tissue - found inside the body (e.g. airways, blood vessels, intestines, walls of organs) & outside of body (skin)
epithelial cells can be determined by their shape
cuboidal
columnar
squamous (squash)
epithelial tissue can be determined by number of layers
simple - 1 layer of cells thick
stratified - 2 or more layers of cell thick
simple squamous epithelium
single layer
very thin of flat cells lining surface
thin exchange surface for quick diffusion
found in lining of alveoli
allows rapid diffusion of O2 into blood
basement membrane acts as an attachment point for cells & contains blood vessels to supply the nutrients required by the cells & to transport waste substances away
ciliated epithelium
example of simple columnar epithelium
layer of cells covered in cilia which move in a rhythmic manner
lines surface where substances must be moved e.g. line of trachea where mucus needs to be swept away from lungs
goblet cells are also present - releasing mucus
Connective tissue
is wildly distributed in the body its function is to hold together other tissues & organs
consists of non-living extracellular matrix containing proteins (collagen & elastin) & polysaccharides (such as hyaluronic acid, traps water). This matrix separates the living cells within the tissue & enables it to withstand forces such as weight
blood, bone, cartilage, tendons, ligaments & skin are examples of connective tissue
cartilage
immature cells in cartilage are called chondroblasts
divide by mitosis & secrete the extracellular matrix
once matrix is synthesized the chondroblasts become mature, less active chondrocytes, which maintain the matrix
cartilage is not vascularised (not supplied with blood vessels) the cells in cartilage tissue receive nutrients by diffusion from tissue fluid forced out of blood vessels into the underlying connective tissue
3 types of cartilage
fibrous cartilage
elastic cartilage
hyaline cartilage
connective tissue
hyaline cartilage
found
forms the embryonic skeleton
covers ends of long bones in adults
joins ribs to the sternum
found in the nose
found in trachea (C-shaped rings that keep the trachea open)
found in the larynx
fibrous cartilage
found
occurs in discs between vertebrae in the spine & knee joints
elastic cartilage
found
makes up the outer ear (pinna)
makes up the epiglottis (flap that closes over the larynx when you swallow
Muscle tissue
well vascularised (many blood vessels)
muscles are called fibres - they are elongated & contain special organelles called myofilaments made of the proteins actin & myosin
these myofilaments allow the muscle tissues to contract
function of muscle tissues is to allow movement
3 types of muscle tissue;
cardiac muscle
makes up walls of he heart & allows the heart to beat & pump blood
smooth muscle
occurs in the wall of intestine, blood vessel, uterus & urinary tracts & it propels substances along these tracts
skeletal muscle
packaged by connective tissue sheets, joined to bones by tendons, when these muscles contract that cause bones to move
Nervous tissues
include the brain, spinal chord (CNS) & peripheral neurones (PNS)
function is to transmit electrical impulses around the body
cells form the central nervous system (CNS) & peripheral nervous system (PNS)
organ & organ systems in animals
organ = collection of tissues working together to perform a function/related function
organ system = a number of organs working together to carry out an overall life function
https://docs.google.com/document/d/1rXx1tDhCjEedWQFJddEaKOjFS6ywwfD2XAq_h0mpia0/edit
