Basic Tissues

Question 1

What is the fundamental structural and functional unit of the body?

Answer 1

Cell

Question 2

What is a collection of cells that perform a particular function?

Answer 2

Tissue

Question 3

What consists of multiple tissues that work together to perform a particular function?

Answer 3

Organ

Question 4

What is a group of organs with a collective function called?

Answer 4

Organ System

Question 5

What is defined as one complete individual?

Answer 5

Organism

Question 6

What are the four basic types of tissues?

Answer 6

• Epithelia
• Connective tissue
• Muscle
• Nervous

Question 7

What are the important characteristics of epithelia?

Answer 7

• Attachment
• Avascularity
• Regeneration
• Polarity (apical and basal)
• Basement membrane

Question 8

What is the classification of epithelia based on?

Answer 8

Number of cell layers and the shape of the cells in the most superficial layer

Question 9

What are the two classifications based on the number of cell layers?

Answer 9

• Simple – one layer
• Stratified – two or more layers

Question 10

What are the three shapes of epithelial cells?

Answer 10

• Squamous (flat)
• Cuboidal (cube)
• Columnar (rectangle)

Question 11

What is the major function of simple squamous epithelium?

Answer 11

Exchange of nutrients and gases

Question 12

Where is simple squamous epithelium located?

Answer 12

Blood vessels, alveoli

Question 13

What is the major function of keratinised stratified squamous epithelium?

Answer 13

Protection, barrier (waterproof due to keratin)

Question 14

Where is keratinised stratified squamous epithelium located?

Answer 14

Skin

Question 15

What is the major function of non-keratinised stratified squamous epithelium?

Answer 15

Protection, barrier

Question 16

Where is non-keratinised stratified squamous epithelium located?

Answer 16

Oral cavity (not hard palate or gums), oesophagus

Question 17

What is the major function of simple cuboidal epithelium?

Answer 17

Secretion and absorption

Question 18

Where is simple cuboidal epithelium located?

Answer 18

Glands, kidney tubules

Question 19

What are the surface modifications of simple columnar epithelium?

Answer 19

Microvilli

Question 20

What is the characteristic of pseudostratified ciliated columnar epithelium?

Answer 20

Tall cells

Appears stratified but all cells touch the basement membrane

ONLY 1 LAYER

Question 21

What do intercellular junctions do?

Answer 21

Bind one cell to another

Question 22

What are the types of intercellular junctions?

Answer 22

• Desmosomes
• Hemidesmosomes
• Tight junctions
• Gap junctions

Question 23

What are desmosomes?

Answer 23

Very strong connections between adjacent cells that resist stretching and twisting

Question 24

What do tight junctions prevent?

Answer 24

Passage of water and solutes between cells

Question 25

What is the function of gap junctions?

Answer 25

Cells held together by an interlocking membrane proteins containing a central pore Allows movement of small molecules and ions between cells Found in cardiac muscles

Question 26

What do hemidesmosomes do?

Answer 26

Attach cells to the basement membrane Stabilises the position and anchor cells to the underlying tissue

Question 27

What are the functions of connective tissue?

Answer 27

* Forms a structural framework for the body * Supports, surrounds, and interconnects other tissue types * Protects delicate organs * Transports fluids and dissolved materials * Stores energy reserves * Defends body from microorganisms

Question 28

What is connective tissue composed of?

Answer 28

Cells within an extracellular matrix

Question 29

What is the main cell type in connective tissue that synthesizes the extracellular matrix?

Answer 29

Fibroblasts

Question 30

What are the two classifications of connective tissue?

Answer 30

* Specialised connective tissue * Connective tissue proper

Question 31

What are examples of specialised connective tissue?

Answer 31

* Blood * Bone * Cartilage

Question 32

What characterizes loose (areolar) connective tissue?

Answer 32

Contains lots of ground substance Few fibres (collagen & elastic) Variety of cells - fibroblasts (in all tissue), adipocytes, macrophages *Found under the epithelium that covers and lines the body surfaces*

Question 33

Where is dense irregular connective tissue found?

Answer 33

In the dermis

Question 34

What does dense regular connective tissue consist of?

Answer 34

Little ground substance Many densely packed bundles of collagen fibres arranged haphazardly (any direction) Few cells

Question 35

What are the three types of muscle tissue?

Answer 35

* Skeletal * Smooth * Cardiac

Question 36

What are the similarities between all muscle types?

Answer 36

* Elongated parallel to axis of contraction * Numerous mitochondria * Contractile elements

Question 37

What is the function of skeletal muscle?

Answer 37

Moves and stabilises the skeleton Forms sphincters in digestive and urinary tracts Involved in respiration

Question 38

What characterizes skeletal muscle cells?

Answer 38

- Long, cylindrical cells (length of whole muscle) - Striated (striped) - Multinucleated (more than one nucleus) - Innervated by somatic nervous system (voluntary nervous system)

Question 39

Where is smooth muscle located?

Answer 39

In the walls of organs, blood vessels, and airways

Question 40

What characterizes cardiac muscle?

Answer 40

Branched muscle fibres Striated 1-2 central nuclei Intercalated discs Innervated by the autonomic nervous system

Question 41

Where is epithelia located?

Answer 41

- cover surfaces i.e. skin, mouth, heart lining - lines cavities and tubes - forms glands

Question 42

What shape are simple squamous cells?

Answer 42

One layer of cells Flat cells- oval shaped nuclei

Question 43

What shape are Keratinised stratified squamous cells?

Answer 43

Flat surface cells - oval shaped nuclei Many layers = stratified Keratin sits on surface of epithelium

Question 44

What shape are non-keratinised stratified squamous cells?

Answer 44

Flat surface cells - oval shaped nuclei Many layers = stratified Keratin sits

Question 45

What shape are simple cuboidal epithelium cells?

Answer 45

Square cells - round nuclei One layer

Question 46

What shape are simple columnar epithelium cells?

Answer 46

Tall cells - oval, basally located nuclei One layer

Question 47

What are the major functions of simple columnar epithelium cells?

Answer 47

Absorption & secretion

Question 48

Where are simple columnar epithelium cells located?

Answer 48

Gastrointestinal tract

Question 49

What are modifications of pseudostratified ciliated columnar epithelium cells?

Answer 49

Have cilia and goblet cells (produce mucus)

Question 50

Where are pseudostratified ciliated columnar epithelium cells located?

Answer 50

Trachea and large respiratory airways

Question 51

What are the functions of pseudostratified ciliated columnar epithelium cells?

Answer 51

Mucociliary escalator

Question 52

What does the extracellular matrix consist of?

Answer 52

- Ground substance - Tissue (extracellular) fluid - Fibres; collagen, reticular & elastic

Question 53

What is connective tissue proper?

Answer 53

Fills gaps between organs Classified according to the type, arrangement and abundance of fibres, cells and ground substance I.e. loose areolar, dense irregular, dense regular

Question 54

What does dense irregular connective tissue do?

Answer 54

Resists excessive stretching and distension

Question 55

Where is dense regular connective tissue found?

Answer 55

In tendons (muscles) and ligaments

Question 56

What does dense regular connective tissue consist of?

Answer 56

Little ground substance Many densely packed bundles of collagen fibres arranged in parallel rows Few cells

Question 57

What is the role of smooth muscle?

Answer 57

Gastrointestinal movement Alters diameter of airways and blood vessels

Question 58

What characterises smooth muscle?

Answer 58

- Short, fusiform (spindle shaped) cells - Non-striated - Single, centrally located nucleus - Innervated by autonomic nervous system (involuntary)

Question 59

Where is cardiac muscle found?

Answer 59

Found in the heart wall Helps to circulate blood and to maintain blood pressure