Exercise 5: Histology and Body Membranes

Question 1

Tissue

Answer 1

A collection of similar cells grouped together to function as unit.

Question 2

Four types of tissue.

Answer 2

1. ) Epithelial Tissue
2. ) Connective Tissue
3. ) Muscular Tissue
4. ) Nervous Tissue

Question 3

Apical Surface

Answer 3

The free or exposed surface of tissue.

Question 4

Basal Surface

Answer 4

Sits on the basement membrane. It is opposite the apical surface of the tissue.

Question 5

Epithelial tissue is characterized on two things:

Answer 5

1. ) Number of layers.

2. ) Shape of individual cells.

Question 6

Avascular

Answer 6

Epithelial tissues are avascular. It does not have its own direct blood supply.

Question 7

Simple Squamous ET

Answer 7

Function: Allows for easy movement of molecules across the membrane via processes such as osmosis and diffusion.

Location: Kidney glomeruli, alveoli of the lungs, lining of the heart, blood vessels, lymphatic vessels, and serous membranes.

Question 8

Simple Cuboidal ET

Answer 8

Function: Secretion and absorption.

Location: Kidney tubules, small ducts and glands, thyroid gland, and covering the ovary.

Question 9

Simple Columnar ET

Answer 9

Function: Absorption, secretion and protection.

Location: Lining the stomach, intestines, gallbladder, ducts of large glands, small bronchi, and uterine tubes.

**Digestive tract lining possesses microvilli (brush border). They are short slender cell processes that increase the surface area available for the absorption of nutrients.

**Bronchi and uterine tube lining are ciliated. Used to propel mucus in the bronchi and ova in the uterine tubes.

Question 10

Stratified Squamous ET, Keratinized

Answer 10

Function: Upper layers are filled with keratin, a hard protein. Designed for protection against pathogens, abrasion and chemicals.

Location: Epidermis of skin.

Question 11

Stratified Squamous ET, Non-Keratinized

Answer 11

Function: Protection against underlying tissue. Upper layers of cell do not die and become filled with Keratin.

Location: Esophagus. vagina, mouth, rectum and anus.

Question 12

Stratified Cuboidal ET

Answer 12

Function: Absorption, Secretion and Protection.

Location: Ducts of sweat glands.

Question 13

Stratified Columnar ET (Rare)

Answer 13

Function: Protection and secretion

Location: Protection in the urethra, anus, epiglottis, and pharynx.
Secretion in large ducts of mammary and salivary glands.

Question 14

Pseudostratified Columar ET

Answer 14

Function: Goblet cells secrete mucus and cilia sweep it out of the airways.

Location: Lining the trachea and male reproductive ducts (ciliated and non-ciliated), and ducts of large glands (non-ciliated).

Question 15

Transitional ET

Answer 15

Have larger and rounder apical surface cells.

Function: Distension of organs.

Location: Urinary bladder and uterus.

Question 16

Skeletal Muscle

Voluntary

Answer 16

Function: Allows movement of the skeleton.

Location: Attached to bones.

Question 17

Smooth Muscle (aka visceral muscle)

Involuntary

Answer 17

Function: Moves substances through digestive, urinary, and reproductive tracts, regulates blood vessel diameter and controls the diameter of respiratory passageways.

Location: Hollow organs such as, stomach, urinary bladder, and muscular blood vessels (arteries)

Question 18

Cardiac Muscle

Answer 18

Function: Contraction of the heart muscle.

Location: Heart wall.

Contains intercalated disks: Allow for communication between adjacent cells.

Question 19

Nervous Tissue

Answer 19

Function: generates and conducts an electrical impulse. Carry information from one area of the body to another.

Cell axon= Cell process
Cell dentrites= Cell processes.

Question 20

Connective Tissue Function

Answer 20

Bind, support, protect and fill spaces.

Question 21

Three types of Connective Tissue

Answer 21

1. ) Connective Tissue Proper
2. ) Supporting Connective Tissue
3. ) Fluid Connective Tissue

Question 22

Types of Loose Connective Tissue Proper

Answer 22

1. ) Areolar CT
2. ) Adipose CT
3. )Reticular CT

Question 23

Types of dense CT proper

Answer 23

1. ) Dense regular CT
2. ) Dense Irregular CT
3. ) Elastic

Question 24

Types of Supporting CT

Answer 24

1. ) Hyaline Cartilage
2. ) Fibrocartilage
3. ) Elastic Cartilage
4. ) Compact Bone
5. ) Cancellous Bone

Question 25

Types of Fluid Connective Tissue

Answer 25

1. ) Blood | 2. ) Lymph

Question 26

Matrix

Answer 26

The space between cells. Produced and secreted by the connective tissue cells. Non-cellular, non-living and consists of ground substance and fibers

Question 27

Types of fibers

Answer 27

1. ) Collagen 2. ) Elastic 3. ) Reticular

Question 28

Mesenchyme

Answer 28

* Also called Embryonic CT * Loose, unspecialized tissue that develops in the embryo * Gel-like ground substance * Gives rise to all types of adult CT

Question 29

Areolar CT

Answer 29

* Loose CT * Gel-like matrix with collagen and elastic fibers * Cells include fibroblasts, mast cells, and macrophages * Forms a layer to which epithelial cells may bind, as in the papillary layer of the dermis * Found around capillary networks where it binds and protects the capillaries.

Question 30

Adipose CT

Answer 30

* Loose CT * Composed primarily of adipocytes that store lipids. * Only example of closely packed cells in CT * Sparse matrix and few fibers * Functions as protective padding, thermal insulation and energy storage. * Found in subcutaneous layer of the skin, around the kidneys, eyes, heart, in the breasts, and in the abdominal cavity.

Question 31

Reticular CT

Answer 31

* Loose CT * Matrix consists of reticular fibers arranged in a network and loose ground substance * Main cell type is reticular cells * Forms flexible internal scaffolding that supports other types of cells * Found in lymph nodes, spleen, bone marrow, liver and kidney.

Question 32

Dense Regular CT

Answer 32

* Dense CT * Matrix contains parallel bundles of collagen fibers and little ground substance * Parallel arrangement of collagen bundles gives this tissue great tensile strength in one direction * Main cell type is a fibroblast * Forms ligaments and tendons, where its tensile strength is able to anchor bones to each other and muscles to bones.

Question 33

Dense Irregular CT

Answer 33

* Matrix consists of bundles of collagen fibers and little ground substance * Random arrangement of collagen bundles gives this tissue structural strength to resist tearing in all directions. * Main cell type is a fibroblast * Found in the reticular layer of the dermis, wall of the digestive tract, and fibrous capsules of organs and joints

Question 34

Elastic CT

Answer 34

* Dense CT * Contains a high proportion of elastic fibers * Allows recoil of tissue following stretching * Found in walls of large arteries and the walls of brachial tubes

Question 35

Hyaline Cartilage

Answer 35

* Supporting CT * Very firm matrix containing collagen fibers. Matrix is compressible. Allows tissue to act as a shock absorber and to reduce friction between bony surfaces * Cells are chondrocytes located in cavities called lacunae. * Avascular tissue * Found covering the ends of long bones within joints, costal cartilage, and cartilage of nose, trachea and larynx.

Question 36

Fibrocartilage

Answer 36

* Supporting CT * Matrix contains collagen fibers like hyaline cartilage, but arrangement of fibers is more regular. * Tissue is a shock absorber with high tensile strength * Cells are chondrocytes in lacunae * Found in intervertebral disks, pubic symphysis and menisci of the knee.

Question 37

Elastic Cartilage

Answer 37

*Supporting CT *Firm matrix that has a greater number of elastic fibers *Very flexible *Found in auricle of outer ear and epiglottis Cells are chondrocytes in lacunae

Question 38

Compact Bone

Answer 38

* Supporting CT * Collagen fiber matrix that has been calcified to form hard tissue * Cells are osteocytes which are found in lacunae. Lacunae are interconnected by canaliculi * Contains osteons that consist of a central canal, surrounded by a concentric ring of matrix called lamellae

Question 39

Cancellous Bone

Answer 39

* Supporting CT * Lighter and lese dense than compact bone * Consists of plates of bones called trabeculae that form small, irregular cavities that contain red bone marrow * Deep to compact bone * Red bone marrow produces blood cells in a process called hematopoiesis.

Question 40

Blood

Answer 40

* Fluid CT * Watery matrix called plasma which contains dissolved protein fibers * Blood cells are suspended in plasma * Erythrocytes (red blood cells) transport respiratory gases * Leukocytes (white blood cells) body defense * Platelets involved in blood clotting. * Found within blood vessels

Question 41

Lymph

Answer 41

* Fluid CT * Formed when interstitial fluid is transported from extracellular spaces of body tissue through lymphatic vessels until it ultimely returned to the veins of the cardiovascular system. * contains white blood cells predomininently lymphocytes.