Ch 6 Test Material

Question 1

Organ

Answer 1

the body’s recognizable structures (for example, the heart, lungs, liver, eyes, and stomach) that perform specific functions. An organ is made of several types of tissue and therefore several types of cells.

Question 2

Integumentary System

Answer 2

your body’s outer layer. It’s made up of your skin, nails, hair and the glands and nerves on your skin. Your integumentary system acts as a physical barrier — protecting your body from bacteria, infection, injury and sunlight.

Question 3

Epidermis

Answer 3

Your epidermis is the outermost layer of skin on your body. It protects your body from harm, keeps your body hydrated, produces new skin cells and contains melanin, which determines the color of your skin.

Question 4

Epidermis Job

Answer 4

acts like armor to protect your body from harm, including ultraviolet (UV) radiation, pathogens (bacteria, viruses, fungi and parasites) and chemicals. Skin color.

Question 5

Layers of the Epidermis

Answer 5

stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum. The stratum basale is a single layer of cells primarily made of basal cells.

Question 6

Melanin

Answer 6

Melanin is a complex polymer that originates from the amino acid tyrosine. Melanin is present in human and animal skin to varying degrees, and is responsible for your unique eye, hair and skin color.

Question 7

Skin Color

Answer 7

The epidermis contains melanin, the pigment that gives skin its color. The amount of melanin you have determines the color of your skin, hair and eyes. People who make more melanin have darker skin and may tan more quickly.

Question 8

Dermis

Answer 8

The dermis is a connective tissue layer sandwiched between the epidermis and subcutaneous tissue. The dermis is a fibrous structure composed of collagen, elastic tissue, and other extracellular components that include vasculature, nerve endings, hair follicles, and glands.

Question 9

Dermal Blood Vessels

Answer 9

The blood vessels in the dermis are crucial for the maintenance of the epidermis and epidermal appendages. Nutrients via blood support the epidermis, hair follicles, and sweat glands.

Question 10

Nerve Cell Processes and The Dermis

Answer 10

Nerve endings in your dermis allow you to feel different sensations, like pressure, pain, heat, cold and itchiness. Producing sweat: Your dermis contains sweat glands, which produce sweat when you’re hot or experience stress. Sweat helps control your body temperature (thermoregulation).

Question 11

Dermis and Hair Follicles, Sebaceous Glands, and Sweat Glands

Answer 11

Keeping your skin moist: Your dermis contains sebaceous glands, which secrete an oily lubricant (sebum) that helps keep your skin and hair hydrated and shiny. Producing hair: Your dermis contains hair follicles, which produce hair all over your skin, except the palms of your hands and the soles of your feet.

Question 12

Nails and Keratinized Epidermal Cells

Answer 12

As epidermal cells below the nail root move up to the surface of the skin, they increase in number. Those closest to the nail root get flat and pressed tightly together. Each cell becomes a thin plate; these plates pile into layers to form the nail. As with hair, nails form by keratinization.

Question 13

Hair Follicle

Answer 13

A hair follicle is a tube-like structure (pore) that surrounds the root and strand of a hair. Hair follicles exist in the top two layers of your skin.

Question 14

Keratinization

Answer 14

Keratinization is defined as cytoplasmic events that take place in keratinocytes that move through the different layers of the epidermis to finally differentiate into corneocytes.

Question 15

Hair Color

Answer 15

Human hair color is the pigmentation of human hair follicles and shafts due to two types of melanin: eumelanin and pheomelanin. Generally, the more melanin present, the darker the hair. Its tone depends on the ratio of black or brown eumelanin to yellow or red pheomelanin.

Question 16

Eumelanin and Pheomelanin

Answer 16

There are two types of melanin in mammals, the brownish black eumelanin and the reddish yellow pheomelanin. Eumelanin and pheomelanin are present in human hair and this study was carried out to see whether both pigments are also present in human epidermis.

Question 17

Skin Glands

Answer 17

Both sebaceous glands and sweat glands are organs in your body that protect your skin from becoming too dry.

Question 18

Sebaceous Glands

Answer 18

Sebaceous glands are an organ in your skin that make and secrete sebum. Sebum is a substance that provides a protective coating for your skin to help it retain moisture. Most of your sebaceous glands connect to your hair follicles.

Question 19

Sweat Components

Answer 19

These components are composed primarily of water but also small amounts of minerals (such as sodium, potassium, calcium, and magnesium), metabolites (such as lactate, ammonia, and urea), and unmetabolized pharmaceutical drugs.

Question 20

Swear Glands as Coiled Tubes

Answer 20

Sweat glands are appendages of the integument. There are eccrine and apocrine sweat glands. They differ in embryology, distribution, and function. Eccrine sweat glands are simple, coiled, tubular glands present throughout the body, most numerously on the soles of the feet.

Question 21

Skin Jobs

Answer 21

Provides a protective barrier against mechanical, thermal and physical injury and hazardous substances.
Prevents loss of moisture.
Reduces harmful effects of UV radiation.
Acts as a sensory organ (touch, detects temperature).
Helps regulate temperature.
An immune organ to detect infections etc.
Production of vitamin D

Question 22

Body Temperature, Blood Vessels, and Sweat Glands

Answer 22

The body responds by dissipating heat via: Activating sympathetic cholinergic fibers innervating sweat glands, leading to increased sweat and increased heat loss. Inhibiting sympathetic activity in blood vessels of the skin, causing blood to be shunted to the skin and an increased heat loss.

Question 23

Wound Healing

Answer 23

Haemostasis, inflammation, proliferation, and remodelling.

Question 24

Skin Injuries and Inflammation

Answer 24

In response to tissue injury, inflammatory cells are recruited to wounded tissue. The acute inflammatory response is followed by proliferation of fibroblasts, which are responsible for synthesizing collagen and extracellular matrix.

Question 25

Epithelial Cells Divide to Fill Shallow Cuts in Epidermis

Answer 25

During planar division, epithelial cells typically round up, constrict in the middle to form the cytokinetic furrow, and divide symmetrically with respect to the apicobasal axis to produce two equal daughter cells. In epithelial tissue, keratinocytes travel from the edges of the wound, and slowly grow over the granulating tissue with deep pink color that eventually turns into light purple.

Question 26

Clots Close Deeper Cuts

Answer 26

Capillaries are formed to service the new skin tissue. Contraction occurs at the edges of the wound to reduce the size of the wound. Surface skin cells migrate from one side of the wound to the other, covering the wound with cells to form the new skin. Depending on the injury, the site is left with a scar.

Question 27

Largest Organ in Body by Weight

Answer 27

The first heaviest organ is the skin with a mass of 7.5 and 22 pounds

Question 28

What causes some hair to appear gray in color?

Answer 28

Eumelanin and pheomelanin are found in hair follicles in cells called melanocytes, which produce melanin. As we age, melanocytes decrease in number and less melanin is produced. Fewer melanocytes mean a lack of pigment in the hair, resulting in a silvery-gray color.

Question 29

Why is the skin considered an organ system?

Answer 29

it performs multiple functions to maintain balance within the body

Question 30

What is jaundice?

Answer 30

Jaundice is a condition where your skin, the whites of your eyes and mucous membranes (like the inside of your nose and mouth) turn yellow. This is caused when too much bilirubin builds up in the body.

Question 31

What are the functions of the skin?

Answer 31

Protection against microorganisms, dehydration, ultraviolet light, and mechanical damage

Question 32

How does the skin make body heat?

Answer 32

The blood vessels of the dermis provide nutrients to the skin and help regulate body temperature. Heat makes the blood vessels enlarge (dilate), allowing large amounts of blood to circulate near the skin surface, where the heat can be released. Cold makes the blood vessels narrow (constrict), retaining the body’s heat.

Question 33

Job of arrector pili muscle

Answer 33

The arrector pili muscle pulls the hair into a vertical position. It also elevates the epidermis where the hair enters and depressed the epidermis where the muscle attaches at the papillary layer of the dermis, thus forming small hillocks known as goosebumps.