1 tissues

• What are the four main types of tissues in the body?

  Muscle tissue

  nervous tissue

  connective tissue

  epithelial tissue
• What is the role of nervous tissue, and what are its two main components?

  Nervous tissue is the main component of the nervous system and consists of:

  1. Neurons: Nerve cells that generate and transmit electrical impulses.

  2. Glia: Cells that support, protect, and insulate neurons.
• What is muscle tissue made of, and what is its main function?

  Muscle tissue consists of myocytes (muscle cells) that contract to produce force and motion.
• What are the three types of muscle tissue and their locations?

  1. Skeletal muscle: Attached to the skeleton.

  2. Cardiac muscle: Found in the heart.

  3. Smooth muscle: Lines hollow organs.
• List the functions of muscle tissue.

  Locomotion

  posture (muscle tone)

  generating heat (shivering)

  respiration (breathing)

  circulation (pumping blood)

  facial expression

  regulating sight and hearing

  retaining heat (e.g., hair follicles).
• Give an example of smooth muscle in the body and its role.

  Smooth muscle in the eye controls raising the upper eyelid and dilating the iris.
• What are the six main roles of connective tissue?

  1. Binds and supports.

  2. Provides protection.

  3. Stores essential elements (water, salts, fats).

  4. Provides thermal and electrical insulation.

  5. Transports substances within the body.

  6. Fills spaces between other tissues.
• What are the three main components of connective tissue?

  1. Ground substance.

  2. Fibres.

  3. Cells.
• What is the ground substance in connective tissue, and what does it consist of?

  It is an unstructured material filling the space between fibers and cells. Components include:

  • Interstitial fluid (contains dissolved fluids).

  • Cell adhesion proteins ("biological glue").

  • Proteoglycans and glycoproteins (trap water).
• What are the three types of connective tissue fibers, and what are their properties?

  1. Collagen fibers: Thickest, strong, and abundant.

  2. Reticular fibers: Thin, collagen-like, and flexible.

  3. Elastic fibers: thinnest, Stretch and recoil.
• What are the main types of connective tissue cells and their functions?

  • Fibroblasts: Produce fibers and ground substances.

  • Plasma cells: Produce antibodies.

  • Macrophages: Perform phagocytosis.

  • Mast cells: Produce histamines and heparin for inflammatory responses.
• Give some examples of specialised connective tissue

  Cartilage

  Bone

  Blood

  The humours of the eye
• What are the two types of connective tissue proper?

  1. Loose connective tissue: Areolar and adipose.

  2. Dense connective tissue: Regular and irregular.
• Describe loose areolar connective tissue proper.

  • Soft and pliable.

  • Holds organs in place and binds tissues together.

  • Acts as a reservoir of water and ions.

  • Provides a host for other functions.
• Describe loose adipose connective tissue proper.

  • Made up of adipocytes (fat cells) that store fat droplets.

  • Functions as a shock absorber, thermal insulator, and energy storage unit.
• What is dense regular connective tissue proper, and where is it found?

  • Highly fibrous with fibers running in the same direction.

  • Found in tendons and ligaments for strength and flexibility.
• What is dense irregular connective tissue proper, and where is it found?

  • Contains thicker collagen fibers running in all directions.

  • Found in skin, kidneys, muscles, and bones, though not as strong as regular connective tissue.
• What is the role of covering epithelial tissue?

  Forms boundaries

  lines free surfaces

  provides protection, absorption, and sensation.
• What are some features of covering epithelial tissue

  Usually polyhedral (hexagonal)

  Highly regenerative

  Highly supplied with sensory and motor nerves (innervated)

  Avascular (no blood vessels)
• What are the two surfaces of epithelial cells?

  1. Basal surface: side the epithelial cells sits on the basement membrane.

  2. Apical surface: Free-facing side exposed to external or internal environments.
• What are cilia and microvilli, and what are their functions?

  • Cilia: Aid in movement, hearing, and signaling.

  • Microvilli: Increase surface area for absorption and secretion.
• What are the three shapes of epithelial cells?

  Squamous (flat)

  cuboidal (square-shaped)

  columnar (tall and narrow).
• What is the difference between simple and stratified epithelial tissue?

  • Simple: Single layer for exchange of substances.

  • Stratified: Multiple layers for protection.
• How to name epithelial tissue?

  Use the apical layer to decide on the name
• What is pseudo-stratified epithelial?

  All the cells sit in the basement membrane therefore is considered a simple epithelial
• What is transitional epithelial?

  Shape of the cell changes depending on their environment. Eg when the bladder is full the epithelial cells are squamous and which the bladder is empty the shape of the cells is cuboidal
• What is keratinized stratified squamous epithelium, and what is its function?


  Contains keratin for strength and water resistance, making it impervious to damage.
• What are glandular epithelial tissues involved in?

  The production and secretion of substances like mucus, oils, and hormones.
• What are the three types of glandular epithelial secretions?

  1. Mucous: Thick, sticky substance (e.g., saliva).

  2. Serous: Watery substance (e.g., enzymes).

  3. Sebaceous: Oily substance.
• What are the two types of glands derived from epithelial tissue?

  • Endocrine glands: Ductless, secreting hormones into the bloodstream.

  • Exocrine glands: Secrete substances onto surfaces or into cavities via ducts.
• Features of an endocrine gland

  -most are multicellular organs however a few individual hormone producing cells are scattered around the lining of the digestive tract and the brain

  -usually ductless

  Secretions are varied eg amino acids, peptides, glycoproteins and steroids
• What is a multicellular exocrine gland?

  group of cells which produce and secrete onto surfaces via ducts
• What is a unicellular exocrine gland?

  single cell which both produces and secretes onto the surface via ducts e.g. goblet cells
• Function of a goblet cell and where it can be found

  mucus secreting cell

  -found in the epithelium of the trachea and digestive tube

  - Also found in the eye, skin and other locations
• What is a simple multicellular exocrine gland?

  only consists of 1 duct
• What is a compound multicellular exocrine gland?

  Consists of multiple ducts
• What are the 3 shapes of multicellular exocrine glands

  •Tubular: secretory unit is tube shaped

  • Alveolar: secretory unit is a small hollow cavity

  • Tubuloalveadar: mix of both
• What are the three types of exocrine gland secretion mechanisms?

  1. Merocrine: Product is secreted via exocytosis.

  2. Holocrine: Cell ruptures to release product.

  3. Apocrine: Part of the cell sheds to release product.
• What are examples of multicellular exocrine glands?

  • Simple multicellular glands: E.g., Meibomian glands of the eyelid.

  • Compound multicellular glands: E.g., lacrimal glands (tear production).