Lecture 3 - Organs and Tissues Flashcards
What is a tissue?
A collection of cells of the same type that perform a common function
Name the major tissue types within the body
- Connective
- Muscular
- Nervous
- Epithelial
What does connective tissue do?
- Binds and supports parts of the body
- All have specialised cells, ground substance and protein fibers
- Ground substance is noncellular and ranges from solid to fluid
- The ground substance and protein fibers together make up the matrix of the tissue
What are the 3 main types of connective tissue?
- Fibrous
- Supportive
- Fluid
Types of fibrous connective tissue?
2 types - dense or loose, but both contain fibroblasts cells with a matrix of collagen and elastic fibres
Loose fibrous tissue is found supporting epithelium and many internal organs
Adipose tissue is a special loose fibrous tissue where fat is stored
Types of supportive connective tissue?
Cartilage - cells are in chambers called lacunae
Matrix is solid but flexible
3 types are distinguished by types of fibres
Types of fluid connective tissue?
Blood - contained in blood vessels
Lymph - contained in lymphatic vessels
What do adipose cells release?
Hormone, Leptin which down-regulates appetite
Supportive connective tissue - Cartilage - What are the 3 types that are distinguished by types of fibres? and where are they located?
- Hyaline Cartilage - fine collagen fibres
Located at the nose, ends of long bones and fetal skeleton - Elastic cartilage - more elastic fibres than cartilage fibres
Located at the outer ear - Fibrocartilage - strong collagen fibres
Located at disks between vertebrae
Properties of supportive connective tissue - bone?
- Cells are in chambers called lacunae
- Matrix is solid and rigid that is made of collagen and calcium salts
2 types are distinguished by types of fibres
Compact - made of repeating circular units called osteons which contain the hard matrix and living cells and blood vessels
Located in shafts of long bone
Spongy - an open, latticework with irregular spaces
Located at ends of long bones
Properties of fluid connective tissue - blood?
- Made of fluid matrix called plasma and cellular components that are called formed elements:
- 3 formed elements:
1. Red blood cells - cells that carry oxygen
2. White blood cells - cells that fight infection
3. Platelets - pieces of cells that clot blood
Fluid connective tissue - Lymph
- Matrix is a fluid called lymph
- White blood cells congregate in this tissue
Properties of muscle tissue?
- Allows for movement in the body
- Made of muscle fibres/ cells and protein fibres called actin and myosin
Different types of muscle tissue in humans?
There are 3 different types of muscle tissue in humans
- Skeletal
- Smooth
- Cardiac
Muscle tissue - skeletal
Appearance: Long, cylindrical cells, multiple nuclei striated fibres
Location: Attached to bone for movement
Nature: Voluntary movement
Muscle tissue - smooth
Appearance: spindle-shaped cell with one nucleus, lacks striations
Location: walls of hollow organs and vessels
Nature: Involuntary movement
Muscle tissue - Cardiac
Appearance: branched cells with a single nucleus, striations called darker striations called intercalated disks between cells
Location: heart
Nature: Involuntary movement
Properties of nervous tissue?
- Allows for communications between cells through sensory input, integration of data and motor output
Made of 2 major cells
A. neurons
B. Neuroglia