Tissues

Tissues

a group of cells that are similar in structure and perform common or related functions

The second structural level

Epithelial tissue

cells are close together and vary in shape

A covering or lining tissue
- Organs like the kidneys, heart, intestines and lungs are lines with epithelium
- Also lines inside of organs

Functions:

• Protection from physical and chemical injuries

• Protection against microbial invasion

• Contains receptors which respond to stimuli

• Filters, secretes and reabsorbs materials

• Secretes serous fluids to lubricate structures

Connective tissue

Cells are not close together, separated by non-cellular material (matrix)

• Most abundant & widely distributed tissue

• Found in bone, cartilage, adipose tissue, blood

Functions:

• Provides support for the body and helps to hold all body parts together

• Protects & cushions organs+tissues

• Insulates (fat)

• Transports substances (blood)

Muscle Tissue

Long & thin and can contract to be shorter

• Skeletal:  muscles attached over bones

• Cardiac: makes up the heart

• Smooth: no striations, involuntary. walls of the stomach, intestines etc.

Functions:

• Movement, locomotion, maintains posture, produces heat, facial expressions, pumps bloods, Peristalsis

Nervous Tissue

Made up of neuron’s.

long projections from the cell

• Found in the brain, spinal cord and the nerve (main component of the nervous system)

Functions:

• Regulates and controls body functions

• Generates and transmits nerve impulses

• Supports, insulates and protects impulse generating neuron’s

Mini grid calculations

At 40x magnification - FOV = 4.5mm

At 100x magnification - FOV = 1.8mm

At 400x magnification - FOV = 0.45mm

other structures (organs, systems, organism)

Organs: body structures made up of two or more types of tissue

Systems: a small group of organs that work together to carry out a particular task

Organism: all body systems working together to meet the needs of a functioning organism