Chap 1-9 Flashcards
The structural and functional unit of all living organisms is the
cell
When a cell is observed with a compound light microscope, which of the following structures will be seen?
cell membrane, cytoplasm, and nucleus
The fluid mosaic model is a theory for the structure of
the plasma membrane
Function of the cell membrane or plasma membrane?
- separates the cell from its external environment
- gives the cell a definite size and shape
- controls the movement of molecules from one side of the cell to the other
Basic skeleton of the plasma membrane is formed by
bilayered phospholipid structure
Proteins of the plasma membrane serve all of the following functions
- Breaking down hormones
- Serving as carriers for large molecule transportation
- Binding to neurotransmitters
In some tissues, cells are tightly packed and their cell membranes are connected by a structure known as
Intercellular junction
(anything in between or connecting cells are called junctions)
The fluid-mosaic model of the plasma membrane suggests that
the membrane has rigidity and flexibility
(cell membranes are adaptable to their environment)
Cell adhesion molecules (CAM) are
modified structure to function as sensory receptors
(cells can interact by protein molecules)
The plasma membrane is selectively permeable. This means that
Only certain substances can pass into or out of the cell
What are marker molecules?
primarily steroids
(markers are usually glycloproteins)
The second most abundant of the lipids in the plasma membrane is
cholesterol
(they could also be harmful as they clog arteries and increase blood pressure)
When a sperm cell comes into contact with an egg cell, there is a change in electrical charge across the plasma membrane and various channel proteins close. These channels would be called
voltage-gated channels
(voltage is associated with electrical signals
Osmosis is the diffusion of _____ across a selectively permeable membrane
water
When molecules move from an area of lower concentration to the area of higher concentration and energy is used, it is called
active transport
The aroma of cake baking in the kitchen and reaches the living room. The distribution of this odor throughout the house is an example of
simple diffusion
An increase in _____ will increase the rate of diffusion
temperature
What change/s occur when red blood cells are placed in hypertonic solution
red blood cells lose water and shrink
The movement of a solution across a plasma membrane because of a pressure gradient is called
filtration
The movement of oxygen from a higher concentration in the lungs to a lower concentration in the blood stream is an example of
diffusion
The greater the concentration of a solute in a solution, the greater the
osmotic pressure of the solution
(osmotic pressure is directly proportional to concentration of a solution)
The sodium-potassium pump located in the plasma membrane
actively moves potassium into cells
Cyanide stops the production of ATP. Which of the following process would be affected?
active transport
(active transport is dependent on ATP)
The process of pinocytosis
involves ingestion of liquids rather than particles
What characteristic is shared by simple diffusion and facilitated diffusion
Both involve the movement of a substance from regions of a higher concentration to lower concentration without cellular energy.
In simple diffusion, the rate at which a solute passes through a membrane depends on all of the following
- surface area of the membrane
- temperature of the solution
- concentration difference from one side of the membrane to the other
If a carrier protein were to move both hydrogen and chloride ions from the inside of a cell to the extracellular fluid, and consume ATP in the process, it would be considered a(n)
symport system
All of the following processes can move substances out of a cell
- exocytosis
- simple diffusion
- active transport
Many gland cells release their secretions by means of ___, a process somewhat like reverse endocytosis
exocytosis
White blood cells engulf foreign particles by means of
phagocytosis
Organelles are distinguished from inclusions in that organelles are ___, whereas inclusions are ___.
Functional structures; storage sites for chemical substances
Which of the following cellular components in nonliving?
- mitochondria
- nucleus
- cytoplasm
Cells dispose of worn-out organelles by a process called
autophagy
____ is enclosed in double membranes with cristae extending inward from the inner membrane
the mitochondrion
Endoplasmic reticulum with ribosomes attached to it is called
rough ER
Which function is associated with the rough endoplasmic reticulum
protein synthesis
Which organelle is most active in causing programmed cell death?
lysosomes
Muscle cells contain numerous ___ because of their high demand for ATP
mitochondria
(mitochondria are associated with the production of energy)
What function would immediately cease if the ribosomes of a cell were destroyed?
protein synthesis
When a white blood cell engulfs a foreign particle with its pseudopods, it traps the particle in a bubble called a ___ in its cytoplasm
Vacuole
The following statement about organelles is true
- Depending on the particular cell function, organelles vary in number and type
Vesicles are:
membrane sacs; contain various substances that recently entered or formed in the cell
Microfilaments are:
tiny rods of proteins (actin); cause cellular movement
Microtubules are:
long, slender tubes of globular protein
The function of the golgi apparatus is
packaging and distribution of proteins and lipids
If you compare a cell with a manufacturing plant that exports goods, the cells ___ could be compared to the manufacturing plants shipping department
golgi apparatus
The organelle that protects cells from damaging effects of medications and toxins is
smooth endoplasmic reticulum
A cell uses centrioles in the process of
cell division
A cell with abundant peroxisomes would most likely be involved in
detoxification activitiesO
Organelles in the cytoplasm are embedded in a semitransparent matrix called
cytosol
Tay-Sachs disease involves a cellular defect in
lysosomal enzymes
___ are the only type of cells where flagella are found
Sperm
Cells of the small intestine and kidney tubule have a “brush border” composed of ___, which are cell extensions that increase the surface area
microvilli
Cilia and flagella are distinguished from each other on the basis of
length and numbers
The building blocks of DNA and RNA found in the nucleus of the cell are known as the
nucleotides
The “control center” of the cell is the
nucleus
A structure of the nucleus can be described as
enclosed in a nuclear envelope
In the nucleus, DNA is wrapped within proteins. This structure is known as
chromatin
One function of the nucleus in the cell is to
control and coordinate cellular activities
Elements present in DNA and RNA are
C H O N P
DNA is condensed to form a structure called a ___ in the nucleus
chromosome
Nuceoli
produce ribosomal subunits
Nuclear pores:
allow molecules to move between the nucleus and cytoplasm
Arrange the following sequence:
1) initiated by the RNA, polypeptide chains are made by ribosomes on rough ER
2) Polypeptide chains move through rough ER and then carried in vesicles to Golgi apparatus
3) Golgi apparatus separates and modifies varieties of proteins then packages them into vesicles
4) Vesicles are pinched off from Golgi apparatus carrying newly formed proteins to plasma membrane
The transfer of information from DNA to messenger RNA (m-RNA) is known as
transcription
Which of the following molecules contains the anticodon?
r-RNA
The process of DNA replication is
semiconservative in nature
DNA replication results in two new DNA molecules. Each of these new molecules has
one strand of nucleotides from the parent DNA and only one newly synthesized strand of nucleotides
Cells undergo a series of changes during their life-span known as
cell cycle
What happens by the process of mitosis
new daughter cells with the same number of chromosomes and all other cellular components are produced
DNA synthesis occurs during
the S phase of interphase
Human somatic cells contain _______ chromosomes, while gametic cells contain _______ chromosomes.
46; 23
The major phenomenon and changes during cell division starts within the
nucleus
The process by which cytoplasm divides during cell division is known as
cytokinesis
Meiosis is the process of cell division that occurs in the
gametes (egg and sperm)
By the process of meiosis, a _________ number of chromosomes are produced in the gametes.
haploid
Crossing over
increases the amount of genetic diversity
How many divisional stages occur during meiosis?
2
The process that divides the nucleus during cell division is known as
karyokinesis
Which is the longest and most complex phase during meiosis?
prophase I
Which of the following is characteristic of aging cells?
- golgi apparatus becomes fragmented
- lipid inclusions accumulate
- glycogen-containing structures decrease
A tissue is formed by a group of ____ performing or associated with similar function
cells
There are four primary types of tissues; they are
epithelial, connective, muscular, nervous
muscle tissue is characterized by its
contractility
a tissue specialized for energy storage and thermal insulation is
adipose tissue
which of the following is not one of the four primary classes of tissue
cartilaginous tissue
All permanent connective tissues originate with the ___ of the embryo
mesenchyme
About 90% of all cancers originate from
epithelium
When different varieties of tissues are associated to perform a function they form the structure known as ___
organ
Epithelial tissue is characterized by
tightly packed cells
The various types of epithelium are classified by the
shape of cells and number of cell layers
Epithelial tissue is distinguished from connective tissue, muscular, or nervous tissue by its
basement membrane
Simple epithelium has one layer of cells on the basement membrane, ___ epithelium has more than one layer of cells
Stratified
Which of the following cell organelles would be most important in secretory epithelial cells
Golgi apparatus
Lining of blood capillaries supplying body cells with oxygen and nutrients, are expected to consist of
simple squamous epithelium
Epithelial tissue that can stretch or is subjected to stress would have many
desmosomes
Glands whose ducts have few branches are called
simple
In a(n) ___ gland, the entire cells break down to form the secretion
holocrine
According to their function, there are two major types of epithelial tissue, these are
covering and secretory epithelium
Glands that produce thick, sticky secretion are called ___ glands
mucous
The epithelium that lines the stomach and intestines is
simple columnar
The epithelium that lines the passages of the respiratory and reproductive system is called
pseudostratified columnar epithelium
The secretions of endocrine glands are released directly
into the bloodstream
What is the general function of glands
produce and secrete specialized compounds to control and maintain different body function
A carcinoma is a cancer originating from
epithelium
The following is a function of epithelium tissue
secretion and absorption of molecules
The tissue that forms the inner lining of the respiratory passages is
- pseudostratified
- ciliated
- mucus-secreting
Connective tissue exists in different forms (within the human body) from liquids to very hard solids of the presence of the ___
extracellular matrix
Connective tissue fibers are produced by
fibroblasts
Collagen, elastin, and reticular fibers in connective tissues are formed by
proteins
Extracellular matrix in blood is
plasma
The gel of the extracellular matrix is composed mostly of water and
proteoglycans
Macrophages almost as abundant as fibroblasts are specialized in
phagocytosis
Bone cells are arranged in concentric circles around longitudinal tubes called
osteonic canals
Extracellular matrix in bone is formed by
mineral salts
A general characteristic of connective tissue is that it
consists of cells with much intercellular material between them
Cartilage tissues are likely to be slow in healing following an injury because
they lack direct blood supplies
When cardiac muscle cells are damaged by a heart attack, they are usually replaced by
connective tissue cells
Dense regular collagenous connective tissue would be found in
a ligament
Blood cells are produced in hemopoietic tissue found in
red bone marrow
The only type of cell seen in a tendon is
fibroblasts
The shape of a person’s ear is due mainly to
elastic cartilage
Which of these it NOT connective tissue
muscle
Tendons and ligaments contain the protein
collagen
The secretory cells of a gland are supported by a connective tissue framework called
stroma
The perichondrium is a layer of fibroconnective tissue surrounding
most cartilage
Fetal skeleton in early stages is formed by
hyaline cartilage
Loose connective tissue contains
- collagen and elastin fibers
- myosin and actin fibers
- plasma
Tendons and ligaments are composed primarily of
fibrous connective tissue
Which of the following types of connective tissue is MISMATCHED with its matrix?
cartilage—highly vascular matrix
Muscle tissue cells are contractile, which means they
are specialized in contraction and relaxation
A muscle that is not consciously controlled and has a banded appearance would be described as
striated involuntary
Movement of food through the digestive tract results from the action of
smooth muscle
The only type of muscle with multinucleated fibers is
skeletal muscle
The muscle tissue that can be consciously controlled is
skeletal
Cardiac muscle is found in the wall of the
heart
Which one among the following statement about smooth muscle is TRUE?
- The smooth muscles are responsible for the movements of the internal organs.
- The cells in the smooth muscles have actin, but no striations.
- The muscular cells in the smooth muscles are shorter than the skeletal muscles.
The type of muscle found in the walls of blood vessels is
smooth
A continuous supply of __________ is necessary for muscle contraction.
ATP
Nervous tissue consists predominantly of two cell types:
neurons and neuroglia
Which of the following is associated with nervous tissue?
axon
A unipolar neuron is characterized by the presence of
no dendrites
Which of the following is CORRECTLY matched?
axons—conduct action potentials away from the cell body
What is the function of neuroglial cells in nervous tissue?
support and bind nervous tissue together, and they provide nutrients to neurons
What is the function of nervous tissue?
maintain and coordinate normal body functions
In patients suffering from multiple sclerosis, the _____________ of the neurons are destroyed.
myelin sheath
Three essential components of most neurons are
axon, dendrites and cell body
Which of the following is NOT a characteristic of nervous tissue?
Its intercellular space is filled with collagen.
Inflammatory reactions usually occur in
connective tissue
The formation of scar tissue is most directly caused by
granulation tissue
The abnormal death of a tissue is called
necrosis
Membranes lining body cavities that lack openings to the outside are called
serous
Membranes lining body cavities that do not open to the outside are called
serous
As cells are pushed from the deeper portion of the epidermis toward the surface they
are replaced by dividing cells from below
By covering the whole body surface skin acts as a protective barrier and plays a role in
excretion
Epidermis is characterized by being _______, whereas dermis is distinguished by being _______.
composed of stratified epithelial tissue; composed of connective tissue
The subcutaneous layer in the skin is
composed of loose connective tissue
The skin does not include the
hypodermis
Adipose tissue in the hypodermis
varies in amount from one region to other body regions
The integumentary system has many functions, one of which is
- protection from cancer
- detection of painful stimuli
The outermost layer of epithelium that covers the skin is called the
epidermis
Which of the following functions is associated with the skin?
protection against ultraviolet radiation of the sun
The dermis
is responsible for most of the skin’s structural strength
The layer of epidermis that undergoes mitosis and forms new epidermal cells is the stratum
basale
Intact skin provides protection because
- it forms a physical barrier against the entry of microbes
- its secretions keep the skin slightly acidic
- the skin is capable of excretion of certain waste products
The sloughing off of older cells from the surface of the skin is called
desquamation
The outermost layer of the epithelium in the skin hardens due to deposition of a waterproof protein called
keratin
Which layer of the skin causes the formation of “fingerprints”?
Papillary layer of the dermis
A plastic surgeon would most likely make a skin incision:
Parallel to the cleavage lines.
Which of the following epidermal cells functions in immunity?
Langerhans’ cells
Which of the following acts as the foundation for the skin?
hypodermis
The subcutaneous layer in the skin is
a heat insulator layer which helps to conserve body heat
The integumentary system has many functions, one of which is
detection of painful stimuli
Intact skin provides protection because
it forms a physical barrier against the entry of microbes
Goose-bumps on the skin are due to the contraction of the muscle called
arrector pili muscle.
What is the difference between a hair and a hair follicle?
Dead epidermal cells exist in the hair, whereas a hair follicle is composed of living epidermal cells.
A hair receives its nutrition from
the dermal papilla.
The most superficial layer of the epidermis is
stratum corneum.
Which of the following layers of the epidermis has no nuclei in its cells?
Stratum corneum
Which of the following is true concerning light and dark-skinned races?
Dark-skinned people have the same number of melanocytes as light-skinned people but there is greater melanin production in dark skinned-people.
The activity of apocrine sweat glands
sometimes leads to body odor
Sweat contains
water, salts and wastes
Which one among the following is not a skin gland?
salivary glands
The glands most responsible for cooling the skin are
merocrine
Eccrine sweat glands
respond primarily to elevated body temperature.
Eccrine sweat glands differ from sebaceous glands
- in terms of what is secreted
- in their location in the body
- because sebaceous glands are associated with hair follicles, whereas sweat glands are not
In which of the following regions of the body are apocrine sweat glands most numerous?
axilla and groin
Which of the following statements about the sebaceous gland is true?
- They are associated with the hair follicle.
- Sebaceous glands are also called holocrine glands.
- Secretion from sebaceous gland is called sebum.
Which of the following structures in the hair would contain hard keratin?
Cuticle
Which of the following is true concerning hair growth?
Hair grows for a period of time and then rests and grows again.
When the arrector pili muscle contracts, which of the following happens?
- The hair shaft is pulled perpendicular to the skin surface.
- Movement of the hair follicle causes “goose bumps”.
Which of the following glands produce sweat?
- Apocrine
- Merocrine
Why is it not a good idea for nail technicians to “pull back the cuticles” (eponychium) when manicuring nails?
The cuticle acts as a barrier against infection.
The most active growing region of the nail is called
nail matrix.
Which one among the following statements about nails is true?
Nails protect the ends of fingers and toes.
The nail plate is produced by
specialized epithelial cells.
The primary means by which body heat is lost is
radiation
The ways in which the skin promotes loss of excess body heat are
- dilation of dermal blood vessels
- activation of eccrine sweat glands to release more sweat to skin surface
- loss of heat by radiation, conduction, and convection
An increase in body temperature causes
sweating
An abrasion of the skin results in which of the following?
portal of entry for microorganisms
Which of the following will help cool the body?
evaporation of sweat from the skin’s surface
In cold weather _______ may result from reduced blood circulation through the skin.
cyanosis
Due to the contraction of smooth muscle in the walls of dermal blood vessels
body heat is conserved
By reducing body temperature during hot weather skin helps to maintain
body homeostasis
What determines the color of skin?
amount of melanin produced by melanocytes in the skin
Exposure to ultraviolet light causes the skin to darken by stimulating the production of
melanin.
All of the following substances can contribute to the color of skin. Of these, only ______ is of dietary origin.
carotene
Which of the following layers of the epidermis consists of a single row of columnar cells that undergo mitosis and includes pigment-producing melanocytes?
stratum basale (germinativum)
The melanocytes in very dark skin
contain single, large, pigment granules
Skin color is the result of
heredity or genetic factors.
Which of the following hair colors is the result of a decrease in melanin?
white
Albinism develops due to
inherited mutant gene for melanin.
Light-skinned races such as Caucasians have
approximately the same number of melanocytes as races with darker skins.
Melanin production can be influenced by
- genetics
- exposure to sunlight.
- pregnancy
The skin discoloration most likely to suggest physical trauma is
hematoma
All of the following changes occur in aging skin except:
increased collagen
Which of the following cause “age spots”?
increased melanocytes in certain areas of hands and face
Which of the following groups of people are more likely to get skin cancer as they become older?
- Those who have been frequently over-exposed to the sun.
- Fair skinned blonds and redheads.
- Those who have a pre-existing mole.
Which of the following skin changes is usually associated with aging?
there are additional sweat and sebaceous glands
With aging, individuals tend to feel colder and usually need a higher temperature, especially in the winter because their body
experiences a decrease in the thickness of their subcutaneous fat layer
Stretch marks result from
torn collagen fibers
Elderly persons may become less able to maintain stable body temperatures because
their sweat glands are replaced by fibrous tissue and their activity decreases
Some marrow of long bones is termed “yellow” marrow under normal conditions. The function of this is to
store adipose tissue
Some marrow of long bones is termed “red” marrow. The function of this is to
manufacture blood cells
One of the functions of bone is “electrolyte balance.” Which of the following best represents this role?
Bones store calcium and phosphorus and release them into the blood as needed.
Which of the following best describes the role of a lacuna in a bone?
a cavity within a bone to house an osteocyte
Cartilage grows by two mechanisms: interstitial growth and appositional growth. Which pair of terms best describes the two methods?
internal and on the surface
The shaft of a bone is known as the
diaphysis