Tissues Flashcards
Define homeostasis.
Maintenance of a constant internal environment.
Negative feedback _____ variations from the normal and positive feedback _____ variations from the normal.
- Opposes
2. Exaggerates
Stimulus -> Receptor -> _____ -> Effector -> _____
- Control centre
2. Response
Describe the process of positive feedback in blood clotting.
- Damaged cells release chemicals.
- Chemical start a chain reaction that initiates clotting.
- Each step releases more chemicals to accelerate more clotthing.
- Loop ends with formation of a clot.
Describe the roles of epithelia cells.
- Cover exposed surfaces
- Line passageways
- Produce secretions
Describe the roles of connective tissues.
- Fill internal spaces
- Structural support
- Stores energy
Describe the roles of muscle tissues.
Contracts to produce movement.
Describe the roles of neural tissues.
- Conducts electrical impulses
2. Carries electrical information
Epithelial cells can be classified by their number of layers and what?
Shape
If an epithelial cell is said to be a ‘stratified epithelium’, it means what?
Epithelium has multiple layers.
State the 4 shapes epithelial cells can take.
- Squamous
- Cuboidal
- Columnar
- Transitional
At the bottom of an epithelial cell, what is the name of the membrane that lies on top of the basal surface?
Basement membrane.
What is the role of cell junctions in epithelial tissues?
Ensures cells remain like a flat sheet.
What is the top surface of an epithelial tissue called?
Apical surface.
What is the function of microvilli on epithelial tissues?
Finger-like projections that increase surface area for absorption.
What is the function of cilia on epithelial tissues?
Long hair-like projections that sweep to clear passageways.
Describe what squamous epithelial cells look like.
Flat, squashed surface.
State one place where you could find squamous epithelium.
Lining of blood vessles.
Stratified squamous epithelium produces multiple layers for what?
Protection and recovery from abrasion, pathogens, and chemical attacks.
Cuboidal epithelium provide protection and are important for secretion, where can they be found?
Ducts (e.g. kidney tubule).
Stratified cuboidal epithelium function like simple epithelium, state a gland where they can be found.
Sweat gland.
State the function of transitional epithelium.
Changes from one shape to another.
Are transitional epithelium at the start:
a) taller than they are wide
b) wider than they are tall
a) taller than they are wide
Columnar epithelium are taller than they are wide, what does this help with?
Further distance for substances to pass through, so provides more protection than squamous cells.
What types of epithelia cells contain microvilli?
Columnar epithelium
Pseudostratified ciliated columnar epithelium are in contact with what?
Basement membrane.
Stratified columnar epithelium is found in the mouth and nose, what is the function of these epithelium?
Protection.
Exocrine glands secrete ____ the body.
Outside
____ connect to exocrine glands.
Ducts
Exocrine glands are classified according to shape, what are the four shapes?
- Tubular
- Coiled
- Branched
- Alveolar
Define merocrine glandular secretion.
Merely vesicles are discharged.
Define apocrine glandular secretion.
A portion of cytoplasm shed and subsequently regenerates.
Define holocrine glandular secretion.
Whole cells bursts (consists of stratified tissues).
Connective tissue contains what three substances?
- Cells
- Fibres
- Ground substance
What is ground substance?
Component of connective tissue - fluid such as blood/lymph/cartilage gel.
Where are mesenchymal tissues found and what is their function?
Found in embryos.
Can differentiate into different types of cells.
Loose connective tissue is used for what?
Padding
What are the two types of loose connective tissues?
Adipose
Reticular
What is the function of adipose tissue?
Used for storage of energy, insulates and cushions shock.
What is the function of reticular, loose connective tissues?
Tissue which provides supporting framework from its branched.
What are the three type for dense connective tissues?
- Regular
- Irregular
- Elastic
What is the function of regular dense connective tissues.
Provides firm attachment and stabilises contraction.
What is the function of irregular dense connective tissues?
Limits expansion and provides strength to resist forces applied.
What is the function of elastic dense connective tissue?
Allows for more elasticity.
Cushions shock and facilitates expansion and contraction.
What is the name of cells in cartilage?
Chondrocytes
Chondrocytes sit in a gel-like substance called what?
Hyaline cartilage.
Hyaline cartilage reduces friction between bony surfaces, where is it found?
Synovial joints.
Elastic cartilage includes more elastic fibres which allows for what?
Allows ear to return to normal shape after being bent.
Fibrocartilage prevents what?
Bone-to-bone movement.
Where is fibrocartilage found?
Intervertebral discs.
Mucous membrane lines cavities that communicate with the exterior of the body. What types of epithelium are found here?
Ciliated columnated epithelium.
Serous membranes line the internal body cavities, what tissues are found here?
Simple squamous epithelium
Cutaneous membranes line body surfaces, which tissues are found here?
Stratified squamous epithelium
Synovial membranes consist of what two types of connective tissues?
Loose and dense.
What are the three layers of fasciae?
- Superficial
- Deep
- Subserous
The superficial layer of fasciae is found where?
Between skin and organs/muscle.
Deep fascia is composed from dense connective tissue. What does it form?
Strong, fibrous internal framework.
The subserous fascia is found between what?
Serous membranes and deep fascia.
What are the three types of muscle tissues?
- Skeletal
- Cardiac
- Smooth
Which of the three muscle tissue do not have a striated appearance?
Smooth
Which of the three muscle tissues is smallest?
Smooth
Which of the three muscle tissues is largest?
Skeletal
How are skeletal muscles controlled and stimulated?
Motor neurones.
How are cardiac muscle cells controlled?
Pacemaker cells.
Cardiac muscle consists of intercalated disks which connect between adjacent cells, what is their function?
Electrical connection.
What cells control smooth muscle?
What can also control smooth muscle, beside cells?
Pacesetter cells.
Hormonal control.