Tissues are groups of cells that work together to perform a specific function in the body. There are four main types of tissues: epithelial, connective, muscle, and nervous.
Epithelial tissue covers the surfaces of the body, lines the cavities and organs, and forms the outer layer of the skin. It protects the body from dehydration, injury, and pathogens.
Connective tissue provides support and structure to the body. It includes bone, cartilage, tendons, ligaments, adipose tissue, and blood. Connective tissue also helps in the transportation of nutrients and waste products.
Muscle tissue is responsible for movement. There are three types of muscle tissue: skeletal, cardiac, and smooth. Skeletal muscle is attached to bones and helps in voluntary movement, while cardiac muscle is found in the heart and is responsible for pumping blood. Smooth muscle is found in the walls of organs and blood vessels, and it helps in involuntary movements.
Nervous tissue is made up of neurons and support cells. It is responsible for transmitting and receiving signals in the body, allowing for communication and coordination of bodily functions.