Skin

Question 1

Body Membranes

Answer 1

Covering and lining membranes

Question 2

Function of body membranes

Answer 2

1. Cover the surface
   Cutaneous membrane (skin)
2. Line body cavities
   Mucous membrane - line body cavities that open to the exterior (nose/ digestive tract/ inside lining of the lungs)
3. line organs, forming protective sheets around them and often providing lubrication to reduce friction
   Serous membranes line body cavities closed to exterior (outside lining of the lungs)

Question 3

Classification of body membranes

Answer 3

1. Epithelial membranes (cutaneous/ mucous/ serious membranes)
2. Connective membranes (synovial membrane)

Question 4

Epithelial membranes are known as

Answer 4

Covering and lining membrane

Question 5

Types of epithelial membranes

Answer 5

Cutaneous membrane
Mucous membrane
Serous membrane

Question 6

Epithelial membrane

Answer 6

each of these membranes contains an epithelial layer combined with an underlying layer of connective tissue.

Question 7

Layers of Cutaneous membrane

Answer 7

Superficial epidermis (stratified squamous epithelium)
Underlying dermis (dense connective tissue)

Question 8

True or False
The cutaneous membrane is exposed to air and is considered a dry membrane.

Answer 8

True

Question 9

Mucous membrane consist of

Answer 9

• Epithelium (the type varies depending on the location(stratified squamous/ simple columnar))
• Lamina propria (loose connective tissue)
• Muscularis mucosae

Question 10

Type of epithelium in the mucousae membrane

Answer 10

Stratified Squamous (mouth/ esophagus)
Simple Columnar (rest of the digestive tract)

Question 11

True or false
The mucousae membrane is a dry membrane

Answer 11

False
Mucosae are typically moist membranes that are continuously bathed in secretions, such as mucus or urine.

Question 12

Function of the epithelium mucousae membrane

Answer 12

Absorption and secretion

While many mucosae secrete mucus, not all of them do. For example, the mucosae of the respiratory and digestive tracts secrete protective, lubricating mucus, whereas the urinary tract’s mucosa does not.

Question 13

Serous membrane

Answer 13

Simple squamous epithelium
A thin layer of areolar connective tissue

Question 14

Layers of serous membrane

Answer 14

Serous membranes occur in pairs.
The parietal layer lines a specific portion of the ventral body cavity wall. It folds in on itself to form the visceral layer, covering the organ(s) in that cavity.
The layers are separated by serous fluid, which allows rhe organs to slide past each other without causing friction, especially in mobile organs (lung, heart)

Question 15

Peritoneum

Answer 15

The serosa lining the abdominal cavity and covering its organs is the peritoneum

Question 16

Membranes of the heart and lungs

Answer 16

Membranes around the lungs are pleura.
Membranes around the heart are pericardium.

Question 17

Synovial membranes are composed of

Answer 17

Loose areolar connective tissue

Question 18

Synovial membranes function

Answer 18

1. Their primary function is to line the fibrous layer surrounding joints.
2. They provide a smooth surface within joints.
3. They secrete a lubricating fluid that reduces friction within the joint.

Question 19

Integumentary system consist of

Answer 19

Skin
Appendages

Question 20

Function of the integumentary system

Answer 20

Protect tissues from different types of damages (mechanical/ chemical/ microbe/ UV/ thermal/ desiccation)
Aids in body heat loss
Aids in excretion of urea and uric acid
Synthesis of vitamin D

Question 21

Protects deeper tissues from mechanical damage (bumps)

Answer 21

Presence of keratin ——> toughens cells
Fat cells ——> cushion blows
Pressure and pain receptors ——> alert nervous system to possible damages

Question 22

Protects deeper tissues from chemical damage (acids and bases)

Answer 22

Has relatively impermeable keratinized cells; contains pain receptors, which alert the nervous system to possible damages

Question 23

Protects deeper tissues from microbe damage

Answer 23

Unbroken surface
Acid mantle (skin secretions are acidic, so they inhibit microbes, such as bacteria)
Phagocytes - ingest foreign substances and pathogens

Question 24

Protects deeper tissues from ultraviolet (UV) radiation (damaging effects of sunlight or tanning beds)

Answer 24

Melanin produced by melanocytes offers protection from UV damage.

Question 25

Protect deeper tissues from therma damage (heat/ cold)

Answer 25

Contain heat/ cold/ pain receptors

Question 26

Protect deeper tissues from dessication (drying out)

Answer 26

Contains a water-resistant glycolipid and keratin

Question 27

Aids in body heat loss or heat retention (controlled by the nervous system)

Answer 27

Heat loss: By activating sweat glands and allowing blood to flush into skin capillary beds so that heat can radiate from the skin surface. Heat retention: By not allowing blood to flush into skin capillary beds.

Question 28

Aids in excretion of urea and uric acid

Answer 28

Contained in perspiration produced by sweat glands. (The skin excretes different types of waste products in sweat)

Question 29

Synthesizes vitamin D

Answer 29

Modified cholesterol molecules in skin converted to vitamin D in the presence of sunlight.

Question 30

Structure of the skin

Answer 30

Epidermis Dermis Hypodermis

Question 31

Epidermis tissue

Answer 31

Stratified Squamous epithelium

Question 32

Function of epidermis

Answer 32

It is capable of keratinization, making it hard and tough.

Question 33

Dermis tissue

Answer 33

Dense connective tissue.

Question 34

Function of the dermis layer

Answer 34

Connects the skin to fat and muscle

Question 35

Blisters

Answer 35

Caused by a burn or friction, seperating the epidermis and dermis layer, allowing interstitial fluid to accumulate in it

Question 36

Hypodermis

Answer 36

Made of adipose tissue (fat)

Question 37

Function of the hypodermis layer

Answer 37

Functions of the subcutaneous tissue: 1. It anchors the skin to underlying organs 2. It provides a site for nutrient (fat) storage 3. It serves as a shock absorber 4. It insulates the deeper tissues from extreme temperature changes occurring outside the body.

Question 38

Most cells present in the epidermis

Answer 38

Keratinocytes

Question 39

Keratinocytes

Answer 39

responsible for producing protein keratin, a fibrous that toughens theepidermis through keratinization.

Question 40

Keratinocytes

Answer 40

Keratinocytes are connected throughout the epidermis by desmosomes

Question 41

Epidermis characteristic

Answer 41

The epidermis is avascular,meaning it lacks its own bloodsupply. (This explains why shaving daily does not cause bleeding despite removing multiple cell layers.)

Question 42

Five layers of epidermis (from the inside to the outside)

Answer 42

1. Stratum Basale 2. Stratum Spinosum 3. Stratum Granulosum 4. Stratum Lucidumin (found only in thick skin) 5. Stratum Corneum

Question 43

Stratum Basale

Answer 43

The stratum basale is the deepest layer of the epidermis. It lies closest to the dermis and, therefore, it is well nourished. Composed of basal keratinocyte stem cells (divide constantly) and then forming the keratinocytes of the stratum spinosum as they migrate superficially.

Question 44

Cells within the stratum basal