Tissue and organ systems Flashcards
Animal structure hierarchy?
Cellular level tissue level organic level organ system level organism level
The cell?
Basic unit of living matter separated from the environment by plasma membrane
Function of heart muscle cell?
to contract and relax in a coordinated way with the other heart muscle cells (branched cells: connections)
What is tissue?
Formed by thousands of cells cooperation to perform a specific function
What is an organ?
Several types of tissues, including muscle tissue, nervous tissue, connective tissue cooperating to perform a specific function
What is a system?
Multiple parts: heart, blood vessels
(arteries, veins, capillaries)
Coordination to carry out a common function: transporting blood throughout the body
What is an organism?
Several systems functioning together as an
integrated, cooperative unit
Higher levels?
Studied in Ecology: population (group of organisms of same species), community (group of organisms of different species)
4 major categories on animal tissue?
- Epithelial tissue (4 types)
- Connective tissues (6 types)
- Muscle tissues (3 types)
- Nervous tissues (2 main cell types)

Epithelial tissue definition?
Sheets of closely packed cells that cover body surfaces and line internal organs
Epithelial tissue location?
Outer surface of Body, lines internal organs (e.g. digestive tract)
Epithelial tissue organisation?
Free surface / other surface anchored to underlying tissues by basement membrane
Epithelial tissue 3 functions?
- Protection: skin protects against fluid loss, physical insult, microbial barrier
- Absorption: Oxygen in the lungs, nutrients in the digestive tract
- Secretion: glands (e.g. tears, sweat)
Classification on epithelial tissue based on number of cells?
Number of cell layers:
simple epithelium = single layer
stratified epithelium = one layer touches basement membrane + additional layers on top
Classification on epithelial tissue based on shape of cells?
Squamous cells (floor tiles) Cuboidal cells (dices) Columnar cells (columns)