A&P Exam 3

What is the resting membrane potential of skeletal muscle cells?

- 90 mV

What are the functions of the skin?

1. Resistance to trauma and infection 2. Other barrier functions, like water, UV radiation and harmful chemicals 3. Vitamin D synthesis 4. Sensation 5. Thermoregulation 6. Nonverbal communication

What is a triad?

A T tubule and two terminal cisterns associated with it

What is voltage (electrical potential)?

A difference in electrical charge from one point to another

What is twitch?

A quick cycle of contraction and relaxation when stimulus is at the threshold or higher

Collagen lends ______ to skin. A. elasticity B. Structure C. Color D. UV Protection

A. Elasticity

What rule should we use in watching for moles or any skin growth?

A: Asymmetry B: Borders C: Color D: Diameter

All muscle contraction depends on ______.

ATP

What neurotransmitter will slow the heart, but stimulates the GI tract to do digestion?

Acetylcholine

What breaks down Ach, allowing for relaxation?

Acetylcholinesterase (AChE)

Thin filament?

Actin, light band, I band

Striations result from the precise organization of ____ and _____ in cardiac and skeletal muscle cells.

Action and myosin

What are the two main pathways of ATP synthesis?

Aerobic respiration and anaerobic fermentation

Cardiac muscle use _______ exclusively.

Aerobic respiration; rich in myoglobin and glycogen

What is white skin due to the genetic lack of melanin?

Albinism

Third-degree burns involve _______ and may require ______.

All of the dermis and often some deeper tissues; skin grafts

What is thinning of the hair or baldness?

Alopecia

What is the growth stage of the hair cycle, which 90% of scalp follicles are at a given time?

Anagen

What are the three stages of the hair cycle?

Anlagen, catagen and telogen

Axillary skin has what type of sweat glands?

Apocrine glands

Endomysium?

Around muscle cell

What are the excitation of smooth muscle?

Autonomic activity, hormones, carbon dioxide, oxygen, pH, temperature, stretch and autorhythmicity

Cardiac muscle receives innervation from where?

Autonomic nervous system (sympathetic and parasympathetic)

Where are the apocrine sweat glands found?

Axillary region, beard in men, groin and anal region

•Sebaceous glands ________. a)are a type of sweat gland b)are associated with hair follicles c)may function in response to touch d)release a watery solution of salt and metabolic waste

B.) Associated with hair follicles

Why do muscle cells shorten?

Because their individual sarcomeres shorten

The dermis is well supplied with ____________.

Blood vessels, sweat glands, sebaceous glands and nerve endings

What is the disagreeable body odor produced by bacterial action on sweat from apocrine glands?

Bromhidrosis.

Eumelanin?

Brownish-black

What is echar?

Burned, dead tissue

The papillary and reticular layers are composed mainly of A. Melanocytes B. Keratinocytes C. Connective tissue D. Adipose tissue

C. Connective tissue

Which of the following is not a function of the Hypodermis? a. Protects underlying organs b. Helps maintain body temperature c. Source of blood vessels in the epidermis d. a site to long-term energy storage

C. Source of blood vessels in the epidermis

Which of the following is not part of the skin? a)Epidermis b)Papillary layer c)Hypodermis Stratum basale

C. hypodermis

Contraction is always triggered by ______ energized by ______ and achieved by _______.

Calcium, ATP sliding filaments

Which muscle has especially large mitochondria?

Cardiac

Cardiac muscle cells are called _______.

Cardiomyocytes

What is the degeneration of the hair cycle?

Catagen

The dermis is composed mainly of _________.

Collagen

_________ makes up hair and nails.

Compact hard keratin

Unnaturally high frequencies produce ______.

Complete (fused) tetanus

Voluntary means subject to _______.

Conscious control

What is blueness due to oxygen deficiency?

Cyanosis

Hair and nails are composed mostly of ________.

Dead, keratinized cells

What cell will act as a macrophage in order to do the phagocytosis?

Dendritic

In smooth muscle, Z discs are absent and replaced by ______.

Dense bodies

The reticular layer is what kind of tissue? What is its function?

Dense irregular connective tissue and it is associated with stretch marks

Fingerprints left on things we touch are associated with our ________.

Dermal papillae

______ are upward, finger-like extensions of the dermis.

Dermal papillae

Hypodermis is a common site of _________.

Drug injections

Need for muscle contraction, or calcium, comes from _____by ways of channels in sarcolemma.

ECF

There are excess sodium Na+ in the _____.

ECF

Which cutaneous glands are concerned with cooling the body?

Eccrine

What are the most numerous skin glands in the adult skin?

Eccrine (merocrine) glands

_____ are downward waves of epidermis.

Epidermal ridges

What are the 2 layers of the skin?

Epidermis and dermis

What are the connective tissue wrappings of skeletal muscle?

Epimysium, perimysium and endomysium

What neurotransmitter will stimulate the heart?

Epinephrine

What is redness to the skin due to increased blood flow to skin?

Erythema

What are two forms of the pigment melanin?

Eumelanin and pheomelanin

What are the universal characteristics of muscle?

Excitability, conductivity, contractility, extensibility and elasticity

What are the four major phases of contraction and relaxation?

Excitation, excitation-contraction coupling, contraction and relaxation

Cardiac muscle is highly resistant to _____.

Fatigue

Damaged cardiac muscle cells repair by

Fibrosis >Unfortunately, after a heart attack, functional muscle is not regenerated

Small motor units?

Fine degree of control, eyes and hand muscles

Deaths from burns result primarily from ________.

Fluid loss, infection and toxic effects of eschar

What are flat, melanized patches?

Freckles

What are tan to black aggregations of melanocytes?

Freckles and moles

Smooth muscle fibers have a _______ shape and only have _____ nucleus located _________.

Fusiform, 1, near the middle of the cell

What is the synaptic cleft?

Gap between axon terminal and sarcolemma

Electrical _____ allow each cardiomyocyte to directly stimulate its neighbors

Gap junctions

What is the carbohydrate thats stored to provide energy for exercise?

Glycogen

What is rigor mortis?

Hardening of the muscles or stiffening of the body beginning 3-4 hours after death. Muscles stay contracted and cannot relax because muscle relaxation requires ATP is ATP is no longer produced after death

What are patches of discolored skin (birthmarks) caused by benign tumors of dermal capillaries?

Hemangiomas

What is bruising or clotted blood under the skin?

Hematoma

Excessive hairiness is called _____.

Hirsutism

There are excess potassium ions in the ______.

ICF

What is the difference of melanin in dark and light skinned individuals?

In dark-skinned individuals, melanocytes produce greater quantities of melanin and melanin breaks down more slowly

Cardiomyocytes are joined at its ends to other cells by _______.

Intercalated discs

How does carotene affect the skin?

It is acquired from egg yolks and yellow/orange vegetables and adds a yellow pigment to the skin

How does hemoglobin affect the skin?

It is the pigment in red blood cells and it adds reddish to pinkish hue of the skin

Increased bilirubin levels cause a skin discoloration called __________.

Jaundice

What is the yellowing of the skin due to bilirubin in blood?

Jaundice

Calluses or corns are the result of accelerated multiplication by ____.

Keratinocytes

Which hair is fine, downy unpigmented hair that appears on the fetus in the last 3 months of development?

Lanugo

What is the most significant factor in skin color?

Melanin

Eccrine glands are also known as _________.

Merocrine glands

Mammary glands produce ______ and only develop during _______.

Milk; pregnancy and lactation

Apocrine glands produce sweat that is _________.

Milky and contains fatty acids

Smooth muscle is capable of ______ and _______.

Mitosis and hyperplasia

What are elevated, melanized patches often with hair?

Moles

Large motor units?

More strength than control

What are the four important functions of muscle?

Movement, maintain body posture and body position, stabilize joints and generate

What is isometric contraction?

Muscle develops tension but does not shorten

Skeletal muscles are also called ______ or _______.

Muscle fibers or myofibers

What are the long protein chords occupying most of the sarcoplasm?

Myofibrils

Myofibrils has __________.

Myofilaments

What is the red pigment, that provides some oxygen needed for muscle activity?

Myoglobin

What are the contractile proteins?

Myosin and actin

Thick filament?

Myosin, dark band, A band

When a muscle or nerve fiber is stimulated, what happens?

Na+ goes inside, causing depolarization: inside of plasma membrane becomes more positive

In an unstimulated cell, there are more _________ on the inside of the membrane than on the outside.

Negatively charged particles

Skeletal muscle never contracts unless stimulated by a ___.

Nerve

Synaptic vesicles contain______.

Neurotransmitters such as acetylcholine

Cardiac and smooth muscle have one ________.

Nucleus

What is sebum?

Oily secretion of the sebaceous glands

Each muscle fiber is supplied by _____ motor neuron.

One

What is a motor unit?

One nerve fiber and all the muscle fibers innervated by it

ATP supply depends on availability _____ and ____.

Oxygen and organic energy sources (glucose and fatty acids).

Cardiac muscles have a built-in ______ that rhythmically sets off a wave of electrical excitation

Pacemaker

What is paleness due to decreased blood flow to the skin?

Pallor

Which skin color is most likely a result of anemia?

Pallor

Where is thick skin found?

Palms of the hands and soles of the feet

What are the two layers of the dermis?

Papillary and reticular layers

An individual using a sharp knife notices a small amount of blood where he just cut himself. Which of the following layers did he have to cut in order to bleed?

Papillary dermis

Second-degree burns involve _____ and may appear to be ______.

Part of the dermis; blistered

What is a synapse?

Point where a nerve fiber meets its target cell

Apocrine glands are inactive until __________.

Puberty

Pheomelanin

Reddish-yellow (sulfur containing)

Contraction is activated by the _________.

Release of calcium from sarcoplasmic reticulum to sarcoplasm and the binding of calcium to Troponin

Loss of positive potassium ions turns the membrane negative again, causing _____.

Repolarization

What is the plasma membrane of a muscle fiber?

Sarcolemma

What is the functional contractile unit of a muscle fiber?

Sarcomere

What is the cytoplasm of muscle fiber?

Sarcoplasm

Which structure stores and releases calcium through channels to activate contraction?

Sarcoplasmic reticulum

What is less/more developed in cardiac muscle?

Sarcoplasmic reticulum less developed, but T tubules are larger and admit ions from the extracellular fluid

The oil of your scalp is secreted by ________ associated with the hair follicles.

Sebaceous glands

What is the longest of all muscle tissue?

Skeletal

What is the body's largest and heaviest organ?

Skin

What constitutes the integumentary system?

Skin and accessory organs Hair Nails Cutaneous glands

Cardiac muscle exhibits very ____ twitches, to give the heart time to expel blood.

Slow

What is the sarcoplasmic reticulum (SR)?

Smooth ER that forms a network around each myofibril

Resting membrane potential maintained by _______.

Sodium-potassium pump

What axons lead to the skeletal muscle?

Somatic motor fibers

What are the five cells of the epidermis?

Stem cells, keratinocytes, melanocytes, dendritic and tactile cells

What kind of tissue is found in the epidermis?

Stratified squamous epithelium

What is the deepest epidermal layer?

Stratum basale

The papillary layer of the dermis is most closely associated with which layer of the epidermis?

Stratum basale; at the bottom

As you are walking down the beach, you see a dead, dry, shriveled-up fish. Which layer of the epidermis keeps you from drying out?

Stratum corneum

What layer of the epidermis consists up to 30 layers of dead cells?

Stratum corneum

What are the layers of the epidermis from top to bottom?

Stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum and stratum basale

What layer is seen only in thick skin?

Stratum lucidum

Langerhans cells are commonly found in the ______.

Stratum spinosum

Apocrine glands respond to ____________.

Stress and sexual stimulation

Alternating light and dark transverse bands are called ______.

Striations

Smooth muscle lacks ____.

Striations

Hypodermis is a ____________ tissue.

Subcutaneous

What is the axon terminal?

Swollen end of a nerve fiber `

What permits the conduction of electrical impulses?

T-tubules

What cell is associated with the sense of touch?

Tactile

What is the resting stage of the hair cycle?

Telogen

High frequencies produce ________.

Temporal summation or incomplete tetanus

What is isotonic eccentric?

Tension remains and muscle lengthens

What is isotonic concentric contraction?

Tension remains contact but the muscle shortens

Which hair is found on the scalp, eyelashes and eyebrows?

Terminal

What surrounds the T tubules?

Terminal cisterns

First-degree burns only involve _______.

The epidermis

What is debridement?

The removal of eschar

What is found and not found on thick skin?

Thick skin has sweat glands but no hair follicles or sebaceous (oil) glands

What kind of skin covers the rest of the body?

Thin skin

The papillary layer is what kind of tissue? What is its function?

Thin zone of Areolar tissue that allows for the mobility of leukocytes and other defense cells. It is rich in small blood vessels

Perimysium?

Tissue around the muscle fascicle (fibers)

Epimysium?

Tissue surrounding entire muscle

Actin contains ___________ and ________.

Troponin and tropomyosin

T or F: Dark and light skinned individuals have the same number of melanocytes.

True

What exposure stimulates melanin secretion and darkens the skin?

UV light exposure

Which hair replaces lanugo by the time of birth? It is also found in 2/3 of hair of women and 1/10 of the hair in men?

Vellus

Muscle fibers and neurons are electrically electrically excitable. Their membranes exhibit _________ in response to stimulation.

Voltage changes

Eccrine glands produce _____________.

Watery perspiration that helps cool the body

What is the neuromuscular junction (NMJ)?

When target cell is a muscle fiber

Sarcomere is segment from _____>

Z disc to Z disc

Cardiac muscles are auto rhythmic meaning ______.

able to contract rhythmically and independently

What are the two kinds of sweat glands?

apocrine and eccrine (merocrine) glands

•Eccrine sweat glands ________ a)Are present on hair b)Are present in the skin throughout the body and produce watery sweat c)Produce sebum d)Act as a moisturizer

b)Are present in the skin throughout the body and produce watery sweat

The dermis houses _______ and _______.

hair follicles and nail roots

The skin discoloration most likely to suggest physical abuse is ______.

hematoma

Cardiac muscles are _____.

involuntary

Smooth muscle is ______.

involuntary, nonstriated

What are the three types of hair?

lanugo, vellus and terminal

What is threshold?

minimum voltage necessary to generate an action potential in the muscle fiber and produce a contraction

Where are dendritic cells found?

stratum spinosum and stratum granulosum

What are the regulatory proteins?

troponin and tropomyosin

What is the latent period?

very brief delay between stimulus and contraction

Skeletal muscle can be classified as __________.

voluntary, striated muscle that is attached to one or more bones.