Year 11 Human Biology - Levels of Organisation

what are the 7 life processes

reproduction, growth, excretion, respiration, nutrition, response and movement

what are the levels of organisation in order

cells, tissues, organs, systems

what is a tissue

group of physically assosciated cells, similar in structure and function and specialty, which work together to achieve a common task

what is an organ

a structure made of 2 or more tissues which work together to perform a specific task

what is a system

a group of organs that work together to perform a large task

what are the 4 tissue types

epithelial, connective, muscle and nervous

describe epithelial tissue

closely packed cells which form sheets, covers surfaces and line cavities. the cells sit on a basal membrane and can be simple or stratified

what are the 3 epithelial cell shapes, with descriptions

cuboidal → a cube

squamois → flat rectangles

columnar → tall rectangles

describe connective tissues

cells and a matrix which bind and support the body

list all connective tissues with examples

dense (tendons), loose (glands), adipose (liquid fat droplet), areolar, cartilage (on bone ends, e.g. ear), blood, and bone

describe muscle tissue

muscle fibre cells which contract, that help body or organs move

what are the 3 muscle tissue types

skeletal, smooth and cardiac

describe skeletal muscle

voluntary

striated

attached to bones

long and cylindrical

many nuclei

describe smooth muscle

involuntary

one nucleus

no striations

in internal organ walls

tapered shape

describe cardiac muscle

involuntary

cylindrical fibres and connecting branches

striated

one nucleus

form network in heart walls

work in sync

branches join with intercollated discs

describe nervous tissue

neurons generate and conduct nerve impluses to communicate

supported by glial cells

have axons and dendrites

found in central nervous system, nerves and sensory organs