Integ Bio: Finals

Tissues

Group of cells with similar structure and function plus extracellular matrix, “glue”

Cytology

Study of individual, normal cells of the body

Histology

Study of tissues

4 Types of Human Tissues

1. Epithelial Tissue

2. Connective Tissue

3. Muscle Tissue

4. Nervous Tissue

Epithelial Tissue

• Covers and lines body surfaces, organs, and cavities.

• Protects against physical, chemical, and biological agents.

• Absorbs and secretes substances.

• Examples: skin, lining of the digestive tract, respiratory tract, and glands.

Connective Tissue

• Supports and connects body structures.

• Provides structural framework, protection, and insulation.

• Transports substances throughout the body.

• Examples: bone, cartilage, blood, adipose tissue, and tendons

Muscle Tissue

• Enables movement and generates force.

• Three types:

  • Skeletal: Attached to bones, voluntary control.

  • Smooth: Found in organs like the stomach and intestines, involuntary control.

  • Cardiac: Found in the heart, involuntary control.

Nervous Tissue

• Receives, processes, and transmits information.

• Composed of neurons (nerve cells) and glial cells.

• Responsible for sensory perception, thought, emotion, and motor control.

Free Cell Surfaces

• Surface not in contact with other cells

• Smooth to reduce friction, Ex. Blood vessels

Microvilli

Increase cell’s surface area

Cilia

Move materials across cells’ surface

Goblet cells

• Produce mucus

• Ex. Stomach, intestine lining, respiratory tract

Glandular Epithelium

Structures that secrete substances onto a surface, a cavity, or into blood such as sweat, saliva, breast milk, digestive enzymes, and hormones.

Exocrine glands

• Glands with ducts

• Ex. Sweat, oil

Endocrine glands

• Secrete their substances directly into bloodstream; ductless glands

• Ex. Thyroid, thymus, pituitary glands

Aerolar Tissue

• Structure: Loosely packed cells and fibers embedded in a gel-like matrix.  

• Function:

  • Provides support and flexibility.  

  • Connects tissues and organs.  

  • Helps in nutrient and waste exchange.  

• Location: Found beneath the epithelia, between the skin and muscles, around blood vessels and nerves.

Adipose Tissue

• Structure: Densely packed adipocytes (fat cells) that store lipids.  

• Function:

  • Stores energy in the form of triglycerides.  

  • Insulates the body.  

  • Cushions organs.  

  • Secretes hormones.  

• Location: Subcutaneous layer, around internal organs, and in specific areas like the buttocks and thighs.

Cartilage

is a firm, flexible connective tissue that plays a crucial role in various parts of the body. It's like a strong, rubbery material that provides support, protection, and flexibility.

Hyaline cartilage

• Location: covers ends of bones

• Structure: some collagen fibers

• Function: reduces friction (cushion)

Fibrocartilage

• Location: between vertebra

• Structure: lots of collagen fibers

• Function: can withstand compression

Elastic cartilage

• Location: ear and tip of nose

• Structure: elastic fibers

• Function: can recoil

Bone

• Hard connective tissue

• Solid calcium carbonate matrix

• 2 Types: Compact & Spongy

Compact Bone

• consist of osteons/haversian system

• Ground of matrix is solid (calcium carbonate

• Osteons consist of central canal that allow blood vessels and nerves to travel through them to supply the osteocytes / bone cells

Spongy bone

• Also known as cancellous bone is composed of spongy, porous, bone tissue that is filled with red bone marrow.

• Mostly concentrated in the vertebrae, ribs, pelvis, and skull, cancellous bone

• Responsible for the production of red blood cells.

Muscle Tissue

• Composed of cells that have the special ability to shorten or contract in order to produce movement of the body parts

• Highly cellular and is well supplied with blood vessels

Skeletal muscle

• striated, voluntary

• Parallel elongated cells (fibers)

• Multinucleated; attached to skeleton

• Light meat, dark meat (stripes)

Smooth muscle

• Visceral, involuntary

• Cells are long and tapered

• No striations; move by peristalsis

Cardiac muscle

• Intercalated disc

• Myogenic

• Branched

Nervous tissue

the main tissue component of the nervous system. It is responsible for coordinating and controlling body functions and activities.

Neurons

• cell of the nervous system

• Transmission of nerve impulses

• Facilitate the transfer of information throughout the body by sending electrochemical signals.

Interneurons

Connect various neurons within the brain and spinal cord

Sensory neurons

Carry signals from the outer parts of your body (periphery) into the central nervous system

Motor neurons

Carry signals from the central nervous system to the outer parts (muscles, skin, glands) of your body.

Neuroglial cells (glial cells / non-neuronal cells)

• Support and protect neurons in the central nervous system (CNS) and peripheral nervous system (PNS).

• play a crucial role in maintaining the environment for neurons to function optimally

Simple Cuboidal

• 1 layer of square-shaped cells

• Secretion

• glands, ovaries, kidneys

Simple Squamous

• 1 layer of flat, tile-like cells

• good for diffusion & filtration

• blood vessels, lungs, heart, kidneys

Pseudostratified Columnar

• 1 layer of tall, narrow cells appears stratified but isn’t

• secretes mucus and propel debris out of respiratory tract (cilia)

• nasal cavity and trachea

Simple Columnar

• 1 layer of tall, narrow cells

• secrete mucus and absorption

• stomach, intestines, resp. tract

Stratified Squamous

• many layers of flat, tile-like cells

• protect and acts as a barrier

• skin, mouth, throat, esophagus

Transitional

• special type of stratified epithelium; changes shape -stretched squamous.

• hold fluids

• urinary bladder