Human Physiology 1

Organ

Composed of 2 or more tissue types which perform a function

System

a group of organs that have a common function. Eg. the nervous or endocrine system

Tissue

Cells that work together to perform a function. Inbetweeon cells there is an extracellular matrix.

Connective tissue

provides structural support and has a protective role. It is mainly made up of the extracellular matrix. Blood, bones and adipose tissue are all connective tissue.

Epithelial tissue

protects the internal environment and acts as a barrier. It is found in the lining of tubes like blood vessles and the gut. It is catagorised based on its shape and layering.

Muscle tissue

Cells that can contract and produce force. Skeletal muscle is responsible for moving the skeleton. Cardiac muscle is found in the heart and smooth muscle is involuntary muscle and is found in the lining of organs.

Nervous tissue

Consists of neurons and glial cells. Can only be found in the central or peripheral nervous system. The cells transmit electrochemical messages through the body.

The nervous system

Made up of the central and peripheral nervous system. It coordinates and controls the body’s functions. It is made up of neurons and glial cells, which support the functioning of the neurons. Neurons transmit electrochemical messages throughout the body through the use of neurotransmitters.

The endocrine system

Made up of endocrine cells that secrete hormones which interact with target cells. Hormones are secreted into the extracellular space and pass into the blood stream. Hormones are made by endocrine glads, such as the thyroid or pancreas.

Cells

the basic unit of all life. all cells have a membrane, the nucleus, a cytoplasm/cytosol and organelles.

Plasma membrane

surrounds the cell. the cell memebrane conists of a semipermeable phospholipid bi-layer with proteins, glycoproteins and glycolipids.

Nucleus

the control centre of the cell. Protects and contains the DNA of the cell. Involved in DNA replication and RNA transcription.

Mitochondira

The powerhouse of the cell. Involved in cellular respiration which produces ATP.

Endoplasmic reticulum

Makes biomolecules. The rough ER has ribosomes attatched to it which allow it to translate mRNA into proteins. The smooth ER has no ribosomes and is important for the packaging and transport of materials.

Golgi apparatus

Packages proteins for export into vesicles that dock with the plasma membrane. The cis-face os where materials go in and get modified. The trans-face is where materials go out.