Week 13- Intro

• Week LO:

  
• Lecture LO:

  
• What is a tissue?

  Collection of cells & their products in which one type of cell predominates
• What is an organ?

  Distinct collection of tissues forming a structure within an animal which is adapted to perform a specific purpose
• What is an organ system?

  Collection of organs & tissues which are related by function
• What are the levels of body organisation?

  
• What are the 3 basic elements of tissues?

  • Cells- 1 type forms majority of the cells & gives tissue type its name
  • Intercellular substances- Produced by the cells & lie in spaces between them
  • Body fluids- Interstitial fluid flows through specialised channels running through the tissue
• What does muscle tissue consist of mainly?

  Muscle cells (myocytes)
• What 3 cellular levels in the embryo do all adult tissues develop from?

  • Ectoderm
  • Endoderm
  • Mesoderm
• How many primary tissues are present in an adult?

  4
• What are the 4 primary types of tissue (vertebrates)?

  • Epithelial
  • Connective (support)
  • Muscle
  • Nervous
• What is the function of tendons?

  • Connect muscle to bone
  • Optimise muscle position & length
• What is the function of ligaments?

  • Connect bone to bone
  • Stabilise joints
• What is the function of aponeurosis?

  • Attaches muscle to bone or other muscle
  • Wide flat sheet rather than round tendon
• Epithelial tissue:

  • Cells adjacent with little matrix
  • E.g, skin (epidermis), lining of hollow organs & tubes, glandular epithelium
• Connective tissue:


  • Abundant extracellular matrix, strong
  • E.g, bone, cartilage, tendon, loose connective tissue
• Muscle tissue:


  • Highly contractile cells create movement
  • E.g, striated, cardiac, smooth
• Nervous tissue:


  • Conduct electrical signals (action potentials) along cell membranes
  • E.g, brain & spinal cord, cranial nerves, peripheral nerves, ganglia
• What is bone?


  Connective tissue containing various cell types- although osteocytes/osteoblasts/osteoclasts predominate
• What cell, tissue & organ does the circulatory system contain?

  • Cardiac muscle cell
  • Cardiac muscle
  • Heart
• What is dense connective tissue?

  • Densely packed collagen bundles with few fibroblasts & other cells in between
  • Fibres arranged in 2 formations: dense regular & dense irregular
• Dense regular formation:


  • Fibres in 1 main direction
  • Fibrous connective tissue e.g, tendons (strong bands of fibrous tissue linking muscles to bone), ligaments (link bone to bone) & vocal cords
• Dense irregular formation:


  • Fibres in random mesh
  • Seen in dermis of skin & capsules of joints & organ capsules of testis & lymph nodes
  • Layers of mostly fascias, serous membranes & aponeuroses
  • E.g, whites of eyes, lense of eyes
• What does the kidney look like?

  Renal- urinary system

  
• What does the heart look like?

  Cardiovascular/circulatory system

  
• What does the stomach look like?

  digestive system

  
• What do the lungs look like?

  Respiratory system

  Pulmonary

  
• What does the liver look like?

  Hepatic

  (green gall bladder)

  digestive system

  
• What does the bladder look like?

  Vesical

  (male)

  urinary system

  
• What do the gonads look like?

  Reproductive system

  left=ovaries

  right=testes

  
• What does the gall bladder look like?

  Cholecystic

  digestive system

  
• What do body cavities look like in the body?

  • thoracic, abdominal & pelvic

  
• Which 3 layers in the embryo do adult tissues develop from?

  • Ectoderm
  • Endoderm
  • Mesoderm

  Gastrulation occurs week 3 (epiblast & hypoblast form 3 layers via differentiation)

  
• Which germ layer gives rise to what?


  :

  
• Which type of collagen is bone made out of?

  Type I
• Why do smooth muscle cells surround blood vessels?

  To give vascular tone
• What is the function of chondroblasts?

  • Secrete type 2 collagen & proteoglycans
  • Forms cartilage template in shape of bone
  • Chondroblasts eventually become surrounded by ECM & differentiate into chondrocytes
• Skin layer diagram:


  :

  
• Which organ concentrates & stores bile?

  Gall bladder
• What is the function of secretin?

  Prevents acid secretion