Anatomy and physiology

Describe the subcutaneous layer

-Not technically considered part of the integument -Stabilizes integument -Permits limited independent movement

Mature bone cells are known as ______________, bone-building cells are called ______________, and ______________ are bone-resorbing cells.

: Mature bone cells are known as osteocytes, bone-building cells are called osteoblasts, and osteoclasts are bone-resorbing cells.

4. What is the difference between a closed fracture and an open fracture?

A closed (simple) fracture is completely internal and there is no break in the skin. An open (compound) fracture projects through the skin. It is more dangerous because of the possibility of infection or uncontrolled bleeding.

The lining of the nasal cavity is normally moist, contains numerous mucous cells, and rests on a layer of areolar tissue. Which type of membrane is this?

The lining of the nasal cavity is a mucous membrane.

What physiological functions are enhanced by the presence of microvilli or cilia on epithelial cells?

The presence of microvilli on the free surface of epithelial cells greatly increases the surface area for absorption or secretion. Motile cilia function to move materials over the surface of epithelial cells.

Lack of vitamin C in the diet interferes with the ability of fibroblasts to produce collagen. What effect might this interference have on connective tissue?

The reduced collagen production resulting from a lack of vitamin C in the diet would cause connective tissue to be weak and prone to damage.

List the two terms for the tissue that connects the dermis to underlying tissues.

The tissue that connects the dermis to underlying tissues is the subcutaneous layer or hypodermis.

A sample of a long bone shows concentric layers surrounding a central canal. Is it from the shaft or the end of the bone?

This sample most likely came from the shaft (diaphysis) of a long bone, as concentric layers of bone around a central canal are indicative of osteons, which make up compact bone.

Why does exposure to sunlight or sunlamps darken skin?

When exposed to the ultraviolet radiation in sunlight or tanning lamps, melanocytes in the epidermis (and dermis) synthesize the pigment melanin, darkening the skin.

. Why does the skin of a light-skinned person appear red during exercise in hot weather?

When skin gets warm, arriving oxygenated blood is diverted to superficial blood vessels to eliminate heat. The oxygenated blood imparts a reddish coloration to the skin.

If a burn on the forearm destroys the epidermis and the deep dermis and then heals, will hair grow again in the affected area?

Where the epidermis and deep dermis are destroyed, new hair will not grow.

31. Identify some age-related factors that affect tissue repair and structure.

With advancing age, the speed and effectiveness of tissue repair decrease, the rate of energy consumption in general declines, hormonal activity is altered, and other factors contribute to changes in tissue structure and chemical composition.

Describe a typical strand of hair.

a typical hair is a keratinous strand produced by epithelial cells of the hair follicle

What happens when the arrector pili muscle contracts?

Contraction of the arrector pili muscle pulls on the hair follicle, making the hair stand erect. The result is sometimes known as "goose bumps."

What is the function of fluids produced by serous membranes?

Serous fluid minimizes the friction between the serous membranes that cover the surfaces of organs and the surrounding body cavity.

A tissue contains irregularly shaped cells with many projections, including some several centimeters long. These are probably which type of cell?

The cells are most likely neurons.

identify the two types of supporting connective tissue.

cartilage and bone.

Why does cartilage heal more slowly than bone?

cartilage is avascular

List five important characteristics of epithelial tissue.

closely bound cells a free surface exposed to the environment or an internal space attachment to underlying connective tissue by a basement membrane avascularity (absence of blood vessels) continual replacement of exposed cells.

List the three types of connective tissues.

connective tissue proper fluid connective tissues supporting connective tissues

Identify the four types of tissue membranes found in the body

cutaneous membrane mucous membrane serous membrane synovial membrane

Damaged skin cells are usually shed in sheets because the cells are held together by

desmosomes

When the body is overheated, the skin responds by

dilating blood vessels

Which type of gland releases its secretions directly into the extracellular fluid?

endocrine gland

Name the two primary types of glandular epithelia.

endocrine glands and exocrine glands

How would you explain to your roomate, who has NEVER taken an A&P class, why superficial paper cut to his index finger did not bleed?

epidermis, the top layer of the skin, is epithelial tissue and has no blood vessels

List the four basic types of tissues in the body.

epithelial, connective, muscle, neural

Which of the following is defined as the permanent replacement of normal tissues by a type of connective tissue?

fibrosis

During intramembranous ossification, which type of tissue is replaced by bone?

fibrous connective tissue in the deep dermis, and in endochondral ossification it is hyaline cartilage

A round opening through the bone that acts as a passageway for blood vessels or nerves referred to as a __________.

foramen

Hair is formed by the repeated divisions of epithelial stem cells in which structure?

hair matrix

A hard ossified bone in an adult actually begins within the embryo as a miniature version composed of __________

hyaline cartilage

A type of intercellular connection in which the outermost lipid portions of two plasma membranes is fused is termed a

tight junction

Identify the three main types of epithelial cell junctions.

tight junctions, gap junctions, and desmosomes

Rickets is a condition marked by a softening and bending of bones that occurs in growing children, as a result of ________ deficiency.

vitaminD3

What is the primary function of any serous membrane?

It minimizes friction between the opposing surfaces when an organ moves or changes shape

How could x-rays of the femur determine if a person has reached full height?

An x-ray of the femur (or any long bone) would indicate whether the epiphyseal cartilage, which separates the epiphysis from the diaphysis, is still present. If present, then growth is still occurring. If it is absent, the bone has reached its full length.

Describe bone remodeling.

Bone remodeling refers to the process whereby old bone is continuously being destroyed by osteoclasts while new bone is being constructed by osteoblasts.

Glands that are located in the passageway of the external ear are called

Cerumen

Several complex joints, including the knee, contain both hyaline cartilage and fibrocartilage. What is the difference between these two kinds of cartilage?

Fibrocartilage has a denser network of collagen fibers and very little ground substance in the matrix as compared to hyaline cartilage

A child who enters puberty several years later than than the average age is generally taller than than average as an adult. Why?

Growth continues throughout childhood. At puberty, a growth spurt occurs that is then followed by the closure of the epiphyseal cartilages. The later puberty begins, the taller the child will be at the start of the growth spurt. So, when growth is completed, the individual will be taller than individuals who began puberty earlier.

How would a bone's strength be affected if the ratio of collagen to calcium increased?

If the ratio of collagen to calcium in a bone increased, the bone would be weaker (but more flexible).

Why would you expect the arm bones of a weight lifter to be thicker and heavier than those of a jogger?

In response to mechanical stress on the arm bones during weight lifting, the bones grow heavier. The arm bones of joggers are lighter because they experience relatively little stress.

Explain the relationship between sunlight exposure and vitamin D3 synthesis.

In the presence of ultraviolet radiation in sunlight, epidermal cells in the stratum spinosum and stratum basale convert a cholesterol-related steroid into vitamin D3.

Describe the location of the dermis

It lies between the epidermis and the hypodermis

Which type of muscle tissue has small, tapering cells with single nuclei and no obvious striations?

Muscle tissue that lacks striations is smooth muscle; both cardiac and skeletal muscles are striated.

Using a light microscope, a tissue appears as a simple squamous epithelium. Can this be a sample of the skin surface? Why or why not?

No. A simple squamous epithelium does not provide enough protection against infection, abrasion, and dehydration. The skin surface has a stratified squamous epithelium.

Voluntary control of muscle contractions is restricted to which type of muscle tissue?

Only skeletal muscle tissue is under voluntary control.

Why is osteoporosis more common in older women than in older men?

Osteoporosis is more common in older women because after menopause, levels of estrogens—sex hormones that play an important role in moving calcium into bones—decrease dramatically, making it difficult to replace calcium lost from bones due to normal aging. In men, decreases in sex hormone (androgen) levels occur at later ages.

What general effects do the hormones PTH, calcitriol, and calcitonin have on blood calcium levels?

Parathyroid hormone (PTH) and calcitriol work together to increase blood calcium levels, whereas calcitonin decreases blood calcium levels.

. How does a plasma (cell) membrane differ from a tissue membrane?

Plasma (cell) membranes are composed of lipid bilayers. Tissue membranes consist of a layer of epithelial tissue and a layer of areolar tissue.

Why are pregnant women given calcium supplements and encouraged to drink milk even though their skeletons are fully formed?

Pregnant women need large amounts of calcium to support bone growth in the developing fetus. If an expectant mother does not take in enough calcium in her diet, her body will mobilize the calcium reserves of her own skeleton to provide for the needs of the fetus, resulting in weakened bones in the mother, as well as an increased risk of fracture.

Some criminals sand their fingertips to avoid leaving recognizable fingerprints. Would this practice permanently remove fingerprints? Why or why not?

Sanding the tips of the fingers will not permanently remove fingerprints. The ridges of fingerprints are formed in skin layers that are constantly regenerated, so these ridges will eventually reappear.

The secretory cells of sebaceous glands fill with secretions and then rupture, releasing their contents. Which method of secretion occurs in sebaceous glands?

Sebaceous glands exhibit holocrine secretion.

If a surgeon makes an incision just inferior to the diaphragm, which body cavity will be opened?

abdominopelvic cavity

Which of the following is NOT a function of the skeletal system?

acting as the main source of body heat

Which type of connective tissue contains primarily triglycerides?

adipose (fat) tissue.

What is the most common skin cancer?

basal cell carcinoma

Would a histologist more likely be considered a specialist in microscopic anatomy or in gross anatomy? Why?

because histologists must use microscopes to observe cells, they are specialists in microscopic anatomy

Why are both skeletal muscle cells and axons also called fibers?

because they are relatively long and slender.

Which two types of connective tissue have a fluid matrix?

blood and lymph

If the activity of osteoclasts exceeds that of osteoblasts in a bone, how will the mass of the bone be affected?

bone mass decreases, because osteoclasts break down or demineralize bone.

gap junctions are most abundant in which of the following?

cardiac muscle and smooth muscle tissue

Name the two pigments in the epidermis

carotene;an orange-yellow pigment, melanin;a brown, yellow-brown, or black pigment.

Define osteopenia.

inadequate ossification and is common to the aging process. It results from decreasing osteoblast activity accompanied by normal osteoclast activity.

Identify the two phases in the response to tissue injury.

inflammation and regeneration.

Which of the following organs converts a precursor molecule into calcitriol, a hormone that is essential for calcium and phosphate absorption?

kidneys

which structure is found in both cartilage and bone?

lacunae

A simple cuboidal epithelium would be found

lining of kidney tubules

Osteocytes

maintain normal bone structure by recycling the calcium salts in the bony matrix around themselves

Which of the following is formed via intramembranous ossification?

mandible

Which is the anatomical term for a passageway through a bone?

meatus

. Where are the capillaries that supply the epidermis located?

papillary layer

Which of the following structures link the blood vessels of central canals with those of the periosteum and marrow cavity?

perforating canals

Identify four essential functions of epithelial tissue

physical protection, controls permeability, provides sensation, and produces specialized secretions.

List the major functions of the integumentary system

protects against environmental hazards, helps control temperature, provides sensory information

Where would you expect to find greater than average melanin production?

shoulders

Identify the three types of muscle tissue in the body.

skeletal muscle, cardiac muscle, and smooth muscle.

Identify the three cell shapes characteristic of epithelial cells

squamous (flat), cuboidal (cube-like), and columnar (rectangular).

Identify the order of the layers that piece of glass would puncture as it passes through the skin on the palm of the hand.

stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale, dermal papillae

A useful technique for long-term drug administration, called transdermal administration, involves putting a sticky, drug-containing patch over an area of thin skin.

stratum lucidum

Name the five major functions of the skeletal system.

support, storage of minerals and lipids, blood cell production, protection, and leverage.

. Identify several functions of connective tissues.

supporting, surrounding, protecting, and interconnecting other types of tissue; (2) transporting fluids and dissolved materials; (3) storing energy reserves; and (4) defending the body from invading microorganisms.

Connective tissue structures that attach muscles to bone are called

tendons