Exam 1 Knowledge Checks

Which of the following best describes the papillae?

Extensions of the dermis into the epidermis, forming ridges of fingerprints.

Smooth, nearly flat articular surface

Facet

The shoulder blades are located anterior to the rib cage

False

This is a joint with collagen fibers spanning the space between bones

Fibrous joint

A ______ is an elongated cleft

Fissure

Round or oval opening through a bone

Foramen

Which of the following is not a projection?

Foramen

A ______ is a shallow depression

Fossa

Shallow, basin-like depression in a bone, serving as an articular surface

Fossa

Name the canals that, in compact bone, are the communication from the outside of the bone to its interior central canals

Volkmann's (perforating) canals

Narrow ridge of bone; less prominent than a crest

Line

The endosteum

Lines the marrow cavity

When the epiphyseal plate is replaced by bone

Long bones have reached their adult length

An extension of a bone making an angle with the rest of the bone structure _____

Ramus

Armlike bar of bone

Ramus

The function of articular cartilage is

To reduce friction and to prevent bony surfaces from contacting one another

Which of the following structures are located in spongy bone?

Trabeculae

A large rough projection called a ______ is a process formed where a tendon or ligament attaches.

Trochanter

Very large, blunt, irregularly shaped process

Trochanter

The fingers are distal to the wrist. Moving proximally from the wrist brings you to the elbow

True

Small rounded projection or process

Tubercle

Large, rounded projection; may be roughened

Tuberosity

What four types of cells populate the epidermis?

-Keratinocytes -Melanocytes -Epidermal dendric cells otherwise known as Langerhans cels -Tactile cells (Merkel cells)

Endochondral ossification begins with the formation of

A cartilage model

Which of the following is the incorrect description of a bone classification?

A sesamoid bone is another example of a Wormian bone because they are short irregular bones.

Any projection or bump is called a ______.

Process

This is part of a structure that includes a fibrous capsule lined by a synovial membrane

Articular cartilage

Describe what happens to an epidermal cell when it divides from a stem cell in the stratum germinativum. What happens to their structure during this movement?

As epidermal cells age they pass through the stratum spinosum, the stratum granulosum, the stratum lucidum (in thick skin) and the stratum corneum. In the process they lose their contents, accumulate large amounts of keratin and die. Ultimately the cells are shed.

From the basement membrane outward, the strata of the epidermis are

Basale, spinosum, granulosum, corneum

Intramembranous ossification

Begins with a connective tissue membrane

Spongy bone is located where

Bones are not heavily stressed; where stress arrives in many directions

A synostosis is a

Bony fusion

Prominence or projection

Process

What are the papillae of the dermal layer made up of?

Collagen fibers, blood vessels, and free nerve endings.

Which bone tissue makes up the hard outer part of bones?

Compact bone

Rounded articular projection

Condyle

During fetal development intramembranous ossification takes place in

Connective tissue membranes

Narrow ridge of bone; usually prominent

Crest

A prominent ridge is called a _____ whereas a low ridge is called a ______

Crest; line

Joints typically located between the ends of adjacent long bones are:

Diarthroses

The process of bone growth at the epiphyseal plate is similar to

Endochondral ossification

The dermal papillae interlock with deep projections of the epidermis. These projections are called.

Epidermal ridges or epidermal pegs

In the typical long bone, large quantities of spongy bone is found in the

Epiphyses

During the final step of endochonral ossification, the centers of the _____ begin to calcify, forming _____ centers

Epiphyses, secondary

Layer where epidermal cell division occurs

Germinativum

These joints are formed by a peg-like process fitting into a socket (for example, in the teeth)

Gomphosis

When cartilage is produced at the epiphyseal side of the metaphysis at the same rate as bone is deposited on the opposite side, bones

Grow longer

Bony expansion carried on a narrow neck

Head

What is the subcutaneous layer just deep to the dermis known as?

Hypodermis

Growth of cartilage in which the chondrocyte within the matrix becomes active and proliferate is known as

Interstitial growth

The skeleton provides several important functions. Which of the following is false with respect to these recognized functions?

It is thought to provide leverage although this has recently been disproven. It only supports movement. The muscles themselves provide the leverage.

What is the chief role of keratinocytes?

Keratinocytes are stratified, squamous, epithelial cells that comprise skin. They produce keratin that provides a barrier by preventing the entry of toxic substances from the environment and the loss of important fluids, etc., from the body. They differentiate as they progress from the basal layer to the skin surface. The normal turnover time for keratinocytes is around 30 days.

Canal-like passageway

Meatus

The belly button is _____ to the hips

Medial

What are Merkel cells and what do they do?

Merkel cells are tactile cells that are present at the epidermal-dermal junction. Shaped like a spiky hemisphere, each tactile cell is intimately associated with a disk like sensory nerve ending. The combination, called a tactile or Merkel disc, functions as a sensory receptor for touch.

What tissue is this layer mostly composed of?

Mostly contains adipose tissue

The cell type which is responsible for basic bone formation is the

Osteoblast

Bone matrix is produced by

Osteoblasts

____ are multi-nucleated giant cells that resorb bone by enzymatic degradation

Osteoclasts

A mature bone cell that is completely surrounded by hard bone tissue

Osteocyte

Name the structure that is contained within the lacuna of living bone

Osteocyte

The most abundant cell in bone is the

Osteocyte

These cells have canaliculi that connect to each other. They are also known as mature bone cells

Osteocyte

Osteoblasts synthesized unmineralized organic bone matrix called

Osteoid

The basic functional unit of compact bone is the

Osteon

The two major regions of the dermis are the superficial ____ layer and the deeper _____ layer.

Papillar; reticular

The layer of the dermis closest to the epidermis

Papillary layer

Which of the following is the best name for the layers of the dermis

Papillary layer and reticular layer

Which of the following structures is continuous with the joint capsule ?

Periosteum--near joints, the periosteum becomes continuous with the connective tissues that lock the bones together.

Define keratin

Refers to a family of fibrous structural proteins that helps give the epidermis its protective properties. Keratin is the key structural material making up the outer layer of human skin. It is also the key structural component of hair and nails.

Space within a bone, filled with air and lined with mucous membrane

Sinus

Which bones are formed by intramembranous ossification

Skull

Sharp, slender, often pointed projection

Spine

Layer where there are 15-30 rows of dead, flat keratinocytes that contain mostly keratin

Stratum corneum

Layer with 3-5 rows of flattened keratinocytes, in which organelles are beginning to degenerate. Contain granules that release lipid-rich water repellent secretion.

Stratum granulosum

Layer that is only present in fingertips, palms, and soles; contains 3-5 rows of flat, dead keratinocytes containing a large amount of keratin

Stratum lucidum

Which epidermal layer is found in thick skin only?

Stratum lucidum

Layer also known as the spiny layer. It contains arm-like processes of melaoncytes and Langerhans cells.

Stratum spinosum

A _____ is a narrow groove.

Sulcus

At, near or relatively close to the body surface

Superficial

What is another name for this tissue and why is it called this?

Superficial fascia because it is superficial to the tough connective tissue of the skeletal muscles.

Perforating canals

Supply blood to the Haversian systems

A synarthrosis located between the bones of the skull is a

Suture

This joint occurs where bones are joined together by fibrous ligaments; they are found in the junctions between the bones of the skull

Sutures

Joint in which bones are joined by fibrocartilage

Symphysis

The anterior articulation between the two pubic bones is

Symphysis

A slightly moveable joint

Syndesmosis

This joint occurs where bones are bound together by an interosseous ligament (for example, between the radius and ulna and the tibia and fibula)

Syndesmosis

The two major components of the integumentary system are

The cutaneous membrane and the accessory structures

Endochondral and intramembranous are terms used to describe

The development of bone

What type of epithelium cells does the epidermis consist of?

The epidermis is a keratinized stratified squamous epithelium

In some cultures, women must be covered completely except for their eyes, when they go outside. Explain why these women may develop bone problems later in life.

The hormone cholecalciferol (vitamin D3) is needed to form strong bones and teeth. When the body surface is covered, UV light cannot penetrate to the blood in the skin to begin vitamin D3 production, resulting in fragile bones.

What is the integumentary system?

The integumentary system includes the skin and accessory structures involving sweat and oil glands, hair and nails. Together these structures make up a complex set of organs that serve several functions, mostly protective. The skin is composed of 2 layers (epidermis and dermis) + a hypodermis

What are melanocytes?

The spider-shaped epithelial cells that synthesize the pigment melanin. They are found in the stratum germinativum and the finger-like processes extend into the stratum spinosum.

What are Langerhans cells and what do they do?

The star-shaped epidermal dendritic (Langerhans) cells are active in the uptake and processing of antigens. They ingest foreign substances and are key activators of our immune system.

Each of the following is a function of the integumentary system EXCEPT

The synthesis of Vitamin C

How many layers are there for thin and thick skin?

There are four layers in thin skin and 5 layers in thick skin

The eponychium

is often called the nail cuticle