Exam 1 Flashcards
Chapters 1-6
Anatomy
Study of normal structure and function
Physiology
Study of functions and their parts
Basic Organism for life?
Cell
What are the levels of organization of living and non-living materials from smallest to biggest form?
Atom>molecule>macromolecule>cell>tissue>organ>Organ system>organism
What is are the three types of homeostasis mechanism?
Receptor
Control center
Effector
What does a receptor do?
Recognizes change within the body.
What does a control center do?
Decision maker that maintains the set point
What does is an effector and what does it do?
Muscle or gland that responds to the control center and causes the necessary change in the internal environment
Three important points about a Negative Feedback?
1) Called negative bc it goes in the opposite direction for current point.
2) Prevents sudden and severe changes.
3) Most Common feedback.
Three important points about Positive feedback?
1) Always Increases instead of decreases
2) Produce unstable conditions and will not lead to homeostasis
3) Least Common
What are three examples of Negative feedback?
Temp
BP
BS
What are three examples of Positive feedback?
Blood clot
Birth of baby (contractions)
Breast feeding
What body cavity contains the brain and the vertebral canal?
Dorsal Body Cavity
What does the Ventral body cavity contain?
Thoracic
Heart
Lungs
Ribs
Digestion
Abdomen
Pelvic
What separates the digestive tract organs from the organs in the chest and aides in breathing?
Diaphragm
Cavity where the heart sets?
Mediastinum
What is a serious membrane?
A thin double membrane that lines the body cavities and organs.
What is the inner layer of serious membrane called and what does it cover?
Visceral Layer
Covers organs
What is the outer layer of the serious membrane called and what does it cover?
Parietal Layer
lines the cavity
T or F
There is fluid in between the two layers of serious membranes.
TRUE
It helps keep the two layers from touching. If they were to touch it causes extreme pain. Viruses can attack this layer.
If the fluid between the two layers of the serious membranes is gone, how long will it take for the fluid to come back?
7-10 days
What organ is also considered a gland?
Pancreas
What are the eight characteristics of life and what do they do?
1) Growth: Increase in cell number and size and increase in body size
2) Reproduction: Production of new cells and organisms
3) Responsiveness: Reaction to a change inside or outside of the body
4) Movement: Change in body position or location; motion of internal organs
5) Respiration: Making energy. Most organisms do it by taking in oxygen and giving off carbon dioxide
6) Digestion: Breaking down food into usable nutrients for absorption into the blood
7) Circulation: Moving chemicals and cells through the body fluids
8) Excretion: Removing waste products
What does the Integumentary System do?
Body covering (Skin)
Protection
Body temperature regulation
Sensory reception
Production of Vitamin D
What does the Skeletal system do?
Support and movement
Framework
Protection
Attachment sites
Storage of inorganic salts
Production of blood cells
What does the Muscular System do?
Support and movement
Main source of body heat,
Posture.
What does the Nervous System do?
Integration and coordination of organ function through nerve impulses and neurotransmitters
rapid short-term effects
What does the Endocrine System do?
Integration and coordination of organ function through chemical messengers called hormones
slower, longer-lasting effects
What does the Cardiovascular System do?
Transportation of gases, nutrients, blood cells, hormones and wastes
What does the Lymphatic System do?
Transportation of fluids from tissue spaces to blood
Carries fats from digestive system to blood, Defends body against infection
What does the Digestive System do?
Receives food
breaks down food
absorbs digestion products
excretes waste
What does the Respiratory System do?
Moves air in and out of body, exchanges gases (oxygen and carbon dioxide) between blood and air; absorbs oxygen.
What does the Urinary System do?
Removes blood wastes, regulates electrolyte & water balance and blood pressure, produces urine and excretes it by transporting it to outside of body
What does the Reproductive System do?
Male and female systems produce and transport sex cells, produce hormones, and produce new like organisms. Female also provides for fetal development and childbirth.
What is the position where a person is standing erect, facing forward, upper limbs at the sides, palms facing forward?
Anatomical Position
Anatomical Position: Superior
Above
Anatomical Position: Inferior
Below
Anatomical Position: Anterior/Ventral
Front
Anatomical Position: Posterior/Dorsal
Back
Anatomical Position: Medial
Toward midline
Anatomical Position: Lateral
Away from midline
Anatomical Position: Bilateral
Both sides (paired structure)
Anatomical Position: Ipsilateral
Hint: think brain
Same Side
Anatomical Position: Contralateral
Hint: think brain
Opposite Sides
Anatomical Position: Proximal
close to point of attachment to trunk
Anatomical Position: Distal
farther from point of attachment to trunk
Anatomical Position: Superficial
close to body surface
Anatomical Position: Deep
more internal
What is the Sagittal section?
longitudinal cut that divides body into left and right portions
What is the midsagittal section?
longitudinal cut that divides body into left and right portions
What is the parasagittal section?
(sagittal section lateral to midline)
divides body into unequal left and right portions
What is the Transverse plane?
Also, Horizontal
divides body into superior and inferior portions
What is the coronal section?
Also, Frontal
longitudinal cut that divides body into anterior and posterior portions
What is the “general” agar because it has a variety of nutrients in it and most microbes will be able to grow on it?
Trypticase Soy Agar (TSA)
What is BAP and what does it do?
Blood Agar Plates
Bacteria can use it as a food source and digest or hemolyze entire blood cells and they leave clear places in the agar where they used up the blood. Beta Hemolysis.
What do you notice about bacteria that indicates it is a cell?
It has a cell membrane and a wall.
What of the following is acellular?
A) Human Cells
B) Bacteria
C) Viruses
D) Fungi
C) Viruses
Why is a virus not considered a cell?
It doesn’t have a covering.
What does bacteria have that an animal cell does not have?
A thick outer cell wall.
Bacteria is also called?
A Prokaryotic cell.
(no nucleus)
Animal cells are also called?
A Eukaryotic cell.
What happens to cells during mitosis?
Regenerate body cells
How long to RBCs live?
120 days
What do smooth endoplasmic reticulum make?
Lipids & Steroids
What process is rough endoplasmic reticulum help in?
Protein synthesis
Describe Staphylococcus bacteria growth pattern.
Spherical and grows in clusters like grapes
(Localized)
Describe the Streptococcus growth pattern.
Spherical enzyme that grows in chains
(can spread)
Describe the growth pattern of Clostridium perfringens.
Rod-shaped that produces gang green and tetanus.
(Anthrax)
Describe the growth pattern of Spirilla.
Spiral shaped organisms
(Don’t see often)
Golgi Apparatus does what?
Transfer- “UPS Store”
What are Centrioles and what do they do for the cell?
A paired like an “X”
They aid in cell division
What do the Mitochondria do for the cell?
What does it mean if there are more vs less in each cell?
It’s the energy for the cell
More means that cell needs more energy vs less means the cell doesn’t need much energy.
What is the Right Upper abdominal region?
Right Hypochondriac Region
What is the Upper Middle abdominal Region called?
Epigastric Region
What is the Left Upper abdominal region called?
Left Hypochondriac Region
What is the Right Middle abdominal region called?
Right Lateral Region
What is the very middle abdominal region called?
Umbilical Region
What is the Left Middle abdominal region called?
Left Lateral Region
What is the Lower Right abdominal region called?
Right Inguinal
What is the Lower Middle abdominal region called?
Pubic Region
What is the Lower Left abdominal region called?
Left Inguinal
What does Collagen do for the tissues?
Strengthen
Define Matter
Anything that takes up space
What are the structures of matter?
Matter
Elements
Atoms
Define Elements
composed of chemically identical atoms
Define Atoms
smallest particle of an element
Atoms are composed of what subatomic particles?
Neutron
Electron
Proton
Proton
Positive Charge
Electron
Negative Charge
Neutron
No charge
Three points of a nucleus in an atom?
1) central part of atom
2) composed of protons and neutrons
3) electrons move around the nucleus
What is an atomic number?
Number of protons in the nucleus of an atom of a specific element.
What is a Mass Number?
The number of protons plus the number of neutrons in one atom.
(Electrons do not b/c they’re light)
What are Isotopes?
Atoms with the same atomic numbers but with different atomic weights .
Same number of protons and electrons but a different number of neutrons.
What are two important key points to remember about Isotopes?
1) Oxygen often forms isotopes (O16, O17, O18)
2) Unstable isotopes are radioactive; they emit subatomic particles
Radioactive Iodine
Can be used to destroy cancerous thyroid gland tissue. This is very effective, because the thyroid gland is the only part of the body that actively transports and metabolizes iodine.
What is an Ion?
An electrically charged atom that gains or loses electrons to become stable
What is a Cation?
A positively charged ion, formed when an atom loses electrons
What is an Anion?
A negatively charged ion, formed when an atom gains electrons
What is an Ionic Bond?
Strong chemical bonds formed when ions of opposite charge attract
What are Covalent Bonds?
Strong chemical bonds, formed between atoms that share electrons.
What is a Molecule?
Particle formed when two or more atoms chemically combine
What is a Compound?
Particle formed when two or more atoms of DIFFERENT elements chemically combine
Define Molecular formulas and give an example.
Depict the elements present and the number of each atom present in the molecule
H2 = a molecule of hydrogen
C6H12O6 = a molecule of glucose
H2O = a molecule of water
Structural formulas
Show how atoms bond and are arranged in various molecules.
One line between atoms means that 1 pair of electrons are being shared (forming single bonds), while two lines indicate that 2 pairs are being shared (forming double bonds).
Nonpolar covalent bonds
Covalent bonds in which electrons are shared equally
Atoms of same element form nonpolar covalent bonds
(C&H)
Polar covalent bonds
Covalent bonds in which electrons are not shared equally
Forms polar molecules with unequal charge distribution. (O&N form with H&C)
(Water)
Hydrogen Bonds
Weak attraction of slightly positive(H) end of one polar molecule to slightly negative (N&O) end of a nearby by polar molecule
Important for Protein and Nucleic Acid Structure
Chemical reactions
occur when chemical bonds form or break between atoms, ions, or molecules.
Reactants
are the starting materials of a chemical reaction: the atoms, ions, or molecules.
Products
are substances formed at the end of the chemical reaction.
Types of Chemical Reactions
Synthesis Reaction: more complex chemical structure is formed
Decomposition Reaction: chemical bonds are broken to form a simpler chemical structure
Exchange Reaction: chemical bonds are broken and new bonds are formed
Reversible Reaction: the products can change back to the reactants
Electrolytes
Substances that release ions in water.
Bases
Substances that release ions that can combine with hydrogen ions.
Salts:
Electrolytes formed by the reaction between an acid and a base
Acids
Electrolytes that dissociate to release hydrogen ions in water.
How is an Electrolyte made?
When an ionically bonded substance (like a salt) is put into water, the charged ions are attracted to the slightly charged ends of the polar water molecules.
This dissociates the substance, and the ions become surrounded by water molecules. The substance is now called an electrolyte, since it can now carry an electric current.
Acidemia occurs when?
blood pH drops to 7.3 through 7.0
Alkalemia occurs when?
blood pH rises to 7.5 through 7.8
Acidosis makes a person feel…
disoriented, fatigued
Acidosis is caused by…
vomiting of alkaline intestinal contents, diabetes, lung disease with impaired CO2 exhalation
Alkalosis makes a person feel….
dizzy and agitated
Alkalosis is caused by…
high altitude breathing, vomiting of acidic stomach contents, high fever, taking excess antacids.
What are buffers?
Chemicals which act to resist pH changes; bind and release H+ ions to regulate pH
Organic molecules:
Contain C and H
Depending on the type, they will dissolve in either water (polar) or organic liquids (nonpolar)
Water-soluble organic compounds do not release ions, and are non-electrolytes
Carbohydrates, proteins, lipids, and nucleic acids
Inorganic molecules:
Generally do not contain C and H
Usually dissolve in water and dissociate, forming ions, and are electrolytes
Water, oxygen, carbon dioxide, and inorganic salts
What does the Nucleus do for the cell?
Contains genetic material which controls the cell’s function.
Produces Ribosomes.
Cytosol?
Fluid portion of the cytoplasm
T or F
All cells have the same number of organelle types.
FALSE
Cells with different specializations have different numbers of particular organelle types.
What major part of the cell is missing in the erythrocyte?
Nucleus
What are the three major parts of the cell?
Nucleus
Cytoplasm
Cell Membrane
What does cytosol do for the cell?
Provides as a medium in which the organelles can function
Hydration
Explain the process of Signal Transduction.
The plasma membrane allows the cell to receive and respond to incoming messages.
Many metabolic reactions take place here.
Which two organic molecules does the endoplasmic reticulum play a role in synthesizing?
Proteins and the synthesis of lipids
An organelle called the ______ functions in protein synthesis.
Ribosomes
Indicate characteristics of vesicles.
are membranous sacs
contain substances that have just entered the cell
contain substances that have been produced by other organelles
The mitochondrion is known as the ______ of the cell as it produces ______.
Powerhouse
ATP
What are microvilli?
Tiny extensions of the cell membrane that absorb substances.
Membranous sacs containing substances that were produced in the cell, such as neurotransmitters or hormones, are called
vesicles
The organelle that modifies proteins synthesized by ribosomes on the RER and packages those proteins for transport is called the
Golgi Apparatus
The process that occurs due to the random movement of atoms, molecules, or ions in air or liquid, from areas of higher concentration to areas of lower concentration, is known as
Diffusion
T or F
When molecules move down a concentration gradient, it means that there is a net movement of particles from a region of lower concentration to a region of higher concentration.
FALSE
Molecules move down a concentration gradient when they move from a region of higher concentration to a region of lower concentration.
Over time, the process of diffusion establishes equal concentrations of solute throughout a solution. This is known as diffusional
equilibrium
Diffusion of a substance across a membrane can happen only if the membrane is ______ to that substance and a concentration gradient ______ across the membrane.
permeable
exists
What would increase the diffusion rate?
Higher Temperatures
Simple diffusion is the movement of molecules from areas of ______ concentration to areas of ______ concentration.
High
Low
Ions that use specific protein channels in the membrane use a process called ______ to move down their concentration gradient across the plasma membrane.
Facilitated Diffusion
Both simple diffusion and facilitated diffusion are ______ transport mechanisms that move molecules ______ a concentration gradient.
Passive
Down
Osmosis is the diffusion of ______ through a selectively permeable membrane.
Water
Which conditions are necessary for the diffusion of a substance to occur across a membrane?
membrane permeability
a concentration gradient
Which type of solution has the same osmotic pressure as the extracellular fluid in the body?
Isotonic Solutions
The passive transport mechanism in which molecules or ions move via carrier or channel proteins from a region of higher concentration to a region of lower concentration is called?
Facilitated Diffusion
T or F
Neither facilitated diffusion nor simple diffusion requires a protein channel or carrier to move molecules across the membrane.
FALSE
Recall that facilitated diffusion requires a protein channel to move molecules across the membrane.
Solutions A and B are separated by a semipermeable membrane. Solution A has more solutes than solution B. In which direction will osmosis occur?
from B to A
Tor F
Active transport processes require cellular energy, usually in the form of ATP, while passive transport processes don’t require cellular energy.
TRUE
Recall that the source of energy in active processes is cellular energy while in most passive processes the source of energy is molecular motion.
Active transport is a process that moves particles through a membrane from a region of ______ concentration to a region of ______ concentration.
Low
High
Why shouldn’t a patient receive an intravenous solution of pure water?
Water is hypotonic to blood cells’ cytosol, so these cells would swell and burst.
Endocytosis takes particles ______ the cell by using ______.
Into
Vesicles
Endocytosis requires energy and utilizes vesicles to take particles that are too large to enter a cell by other means.
Phagocytosis is the process by which cells engulf ______ from the extracellular fluid.
Solid Particles
Which transport mechanisms are classified as active mechanisms?
active transport
endocytosis
exocytosis
The phases of mitosis in the proper order are
1: prophase
2: metaphase
3: anaphase
4: telophase
Which transport mechanisms are classified as passive mechanisms?
osmosis
facilitated diffusion
filtration
diffusion
Which sequence shows the phases of mitosis in proper order, from earliest to latest?
prophase, metaphase, anaphase, telophase
The stage of mitosis in which chromosomes uncoil to become thin chromatin fibers and the nuclear envelope reforms is
Telophase
Specialized cells in the body have ______ of the genes and express ______ of them?
all
some
What are the two parts of the atom?
Nucleus
Shell or Orbital
Where are the electrons located on the atom?
Shell or Orbital
Subatomic particles of the atom?
Protons- carry a charge inside nucleus
Neutrons-no charge inside nucleus
Electrons- negative charge
What’s the difference between inorganic vs organic molecules?
Inorganic= Contain C and H (
Organics= Do not contain C and H (Water Oxygen)
Building blocks of:
Carbohydrates?
Lipids?
Proteins?
Nucleic Acids?
Carbohydrates: glucose
Lipids: Fatty Acids
Proteins: Amino Acids
Nucleic Acids: Nucleus tides
Cell membrane:
Two layers of lipids
Lipids outside layers> Protein is the middle >Heads outward toward water
ER:
Membrane bound sacs
Tubular Transport
Rough= protein synthesis
Smooth= no ribosomes and conducts lipid & steroid synthesis
Vesicles:
Membranous sacs
Contains products of the cell
Store/transport substances
Golgi App:
UPS center
Sacks of flattened membranous sacs
Refines, packages, and delivers proteins made on the RER.
Exocytosis is transport out of the cell, lipids, steroids, and proteins.
Mitochondria:
Membrane bound fluid sacs
ATP Production
Powerhouse of cell
Lysosomes:
Sacs of enzymes
One membrane
Garbage disposals
Bodyguard of cell.
Intracellular digestion
WBC made of these
Passive process: No ATP
Diffusion
Osmosis
Facilitated Diff
Filtration
Active Process: Require ATP
Stores info protein synthesis.
Active trans
Endocytosis
Exactyosis
Transcytosis
Phases of Mitosis
Prophase
Metaphase
Anaphase
Telophase
Cellular Metabolism
Sum of all chem reactions that supports life
Anabolic Vs. Catabolic
Anabolic- making something
Catabolic- Breaking it down
How do Enzymes work?
Enzymes work by Lower activation energy to start reactions.
There are 4 major types of tissues in the body:
- Epithelial tissue
- Connective tissue
- Muscle tissue
- Nervous tissue
Facts need to know about Epithelial Cells?
Covers organs and body surface
Lines cavities and hollow organs
Makes up glands
Have a free surface on outside, and basement membrane on inside
Avascular; nutrients diffuse to epithelial tissue from underlying connective tissue
Cells readily divide;injuries heal rapidly
Cells tightly packed
Epithelial Cell types?
Simple squamous
Simple cuboidal
Simple Columnar
Pseudostratified columnar
Stratified squamous
Stratified cuboidal
Stratified columnar
Transitional (uroepithelium)
Three things to remember about Simple squamous?
1) Single layer of thin, flat cells
2)Substances pass easily through air sacs (alveoli) and capillaries
3)Thin and delicate
What do we need to remember about Simple cuboidal?
1)Single layer of cube-shaped cells
2)Secretion and absorption
3)Lines kidney tubules, thyroid follicles
Simple Columnar cells?
1)Single layer of elongated cells
2)Nuclei usually at same level, near basement membrane
3)Lines uterus, stomach, intestines
Pseudostratified columnar cells?
1)Single layer, but appears layered
2)Nuclei at 2 or more levels
3)Lines respiratory passageways
Stratified squamous cells?
Stratified squamousMany cell layers; thick
Protective layer
Outermost cells are flat
Deeper cells are cuboidal
New cells form, push older cells toward free surface
Outer layer of skin (keratinized)
Lines oral cavity, vagina, anal canal
Stratified cuboidal cells?
2 to 3 layers of cube-shaped cells
More protective than 1 layer
Lines ducts of mammary, sweat, and salivary glands, and pancreas
Stratified columnar?
Top layer of elongated cells
Cube-shaped cells in deeper layers
Lines part of male urethra, ducts of exocrine glands
Transitional (uroepithelium)?
Many cell layers
Cube-shaped and elongated cells
Changes shape with increased tension; stretches
Lines urinary bladder, ureters, and part of urethra
Merocrine glands:
Merocrine glands: Secrete fluid products by exocytosis; salivary and sweat glands, pancreas
Apocrine glands:
Apocrine glands: Lose small part of cell during secretion; mammary and ceruminous glands
Holocrine glands:
Holocrine glands: Release entire cells filled with product; sebaceous glands
Major Cell Types of Connective Tissue:
1) Fibroblasts:
Most common fixed cell.
Large star-shaped cell.
Secrete fibers into extracellular matrix.
2) Macrophages (Histiocytes):
Usually attached to fibers, but can detach and wander
Conduct phagocytosis.
Defend against infection.
Connective Tissue Fibers:
- Collagen Fibers:
Thick threads of collagen, the body’s main structural protein.
Great tensile strength and flexible, slightly elastic.
Found in ligaments and tendons. - Elastic (Yellow) Fibers:
Composed of elastin protein; branching.
Can stretch and return to original shape.
Not as strong as collagen fibers.
Found in vocal cords, respiratory air passages. - Reticular Fibers:
Thin, branching fibers of collagen.
Form delicate, supporting networks.
Found in spleen, liver.
Categories of Connective Tissue:
1) Connective Tissue Proper:
Loose connective tissues:
Areolar
Adipose
Reticular
2)Dense connective tissues:
Dense Regular
Dense Irregular
Elastic
3)Specialized connective tissues:
Cartilage
Bone
Blood
Areolar Connective Tissue:
Forms thin, delicate membranes.
Cells are mainly fibroblasts.
Beneath most epithelia, where it nourishes nearby epithelial cells.
Adipose Tissue:
Adipocytes store fat.
Push their nuclei to one side.
Around kidneys and heart.
Spaces between muscles.
Reticular Connective Tissue:
Composed of thin reticular fibers.
Supports walls of internal organs.
Walls of liver, spleen.
Dense Regular Connective Tissue:
Closely packed collagenous fibers.
Fine network of elastic fibers.
Tendons, ligaments, dermis.
Poor blood supply; slow to heal.
Dense Irregular Connective Tissue:
Randomly organized, thick, interwoven collagenous fibers.
Can withstand tension exerted from different directions.
Dermis of skin.
Around skeletal muscles.
Elastic Connective Tissue:
Abundant yellow elastic fibers.
Some collagenous fibers.
Fibroblasts.
Attachments between bones of spinal column.
Walls of hollow organs, such as large arteries, airways.
Parts of heart.
Elastic quality, stretches.
Cartilage:
A rigid, specialized connective tissue.
3 types of cartilage: Hyaline, Elastic, and Fibrocartilage.
Lacks blood supply; heals slowly.
Covered by perichondrium (connective tissue), which provides some nutrients to the cartilage.
Hyaline cartilage:
Most common type.
Fine collagen fibers.
Ends of bones in joints, nose, respiratory passages.
Embryonic skeleton.
Elastic cartilage:
Flexible, due to elastic fibers in matrix.
External ear, larynx.
Fibrocartilage:
Very tough, due to many collagenous fibers.
Shock absorber.
Intervertebral discs.
Pads of knee and pelvic girdle.
Bone (Osseous Tissue):
Most rigid connective tissue.
Solid matrix, composed of mineral (Ca) salts and collagen.
Supports structures.
Protects vital structures.
Produces blood cells.
Stores and releases Ca, P.
Attachment sites for muscles.
Forms skeleton.
Contain osteocytes (bone cells) in lacunae.
2 types: compact and spongy.
Connective Tissue Types?
Compact Bone:
Osteoblasts deposit matrix in lamellae (layers).
Lamellae occur in rings around central canals.
Osteocytes + matrix + central canal form cylindrical units called.
Osteons:
Osteons are cemented together to form compact bone.
Central canals contain blood vessels; bone is well-nourished, heals more quickly than cartilage.
Blood:
Cells suspended in fluid matrix called plasma.
Red blood cells transport gases.
White blood cells defend again infection.
Platelets help in blood clotting.
Transports substances around body.
Types of Membranes:
3 types of epithelial membranes:
- Serous membranes:
Line body cavities that do not open to outside of body.
Inner linings of thorax and abdomen; covers organs.
Simple squamous epithelium + areolar connective tissue.
Secrete serous fluid for lubrication, reducing friction. - Mucous membranes:
Line cavities and tubes that open to the outside of body.
Lining of digestive, respiratory, urinary, and reproductive tracts.
Epithelium + areolar connective tissue.
Goblet cells secrete mucus. - Cutaneous membranes:
Covers body surface.
Commonly called skin.
Part of integumentary system. - Synovial membranes:
Different from epithelial membranes.
Composed entirely of connective tissue.
Line joint cavities.
Muscle Tissues:
General Characteristics:
Muscle cells are also called muscle fibers.
Contractile; can shorten and thicken.
3 types of muscle tissue: skeletal, cardiac, and smooth.
Skeletal muscle tissue:
Attached to bones.
Striated.
Voluntary.
Multinucleated cells.
Long cylindrical cells.
Stimulated by nerve cells.
Smooth muscle tissue:
Non-striated.
Spindle-shaped fibers.
Walls of hollow organs.
Walls of blood vessels.
Involuntary.
Cardiac muscle tissue:
Only in wall of heart.
Branching cells.
Involuntary.
Striated.
Intercalated discs.
Nervous tissues:
Found in brain, spinal cord, peripheral nerves.
Main cells are neurons, which are specialized for communication, via conduction of nerve impulses (sensory reception, motor control).
Neurons coordinate, integrate, and regulate body functions.
Neuroglia support and nourish neurons.
What is the definition of an organ?
Two or more types of tissues grouped together and performing specialized functions.
Skin is also called?
cutaneous membrane.
What makes up the integumentary system?
skin and its accessory structures (hair, nails, glands, sensory receptors)
2 layers of epithelial tissue overlying connective tissue?
Outer layer is the epidermis.
Deeper layer is the dermis.
Epidermis:
Outer layer
Stratified squamous epithelium
Basement membrane between epidermis and dermis
Dermis:
Inner layer
Thicker of the 2 layers of the skin
Connective tissue
Contains collagenous and elastic fibers
Subcutaneous layer (hypodermis)
Beneath dermis; insulating layer
Areolar and adipose connective tissue
Not considered part of the skin
Contains blood vessels that supply skin
Keratin:
Tough, fibrous, waterproof protein made and stored in the cells
Keratinization:
Process of hardening, dehydration, and keratin accumulation that occurs in epidermal cells as they migrate outward
5 Layers of Epidermis in order from outer to deeper?
1)Stratum corneum: outermost layer; dead, keratinized cells.
2)Stratum lucidum: only in thick skin – palms, soles.
3)Stratum granulosum.
4)Stratum spinosum.
5)Stratum basale/germinativum: deepest, mitotic layer.
Functions of epidermis:
Protects against water loss, harmful chemicals, mechanical injury, pathogens.
Epidermis: Melanocytes
Melanocytes located in the stratum basale produce the dark pigment melanin
Dermis:
Inner layer of skin.
Average of 1 through 2 mm thick.
Contains dermal papillae between epidermal ridges.
Binds epidermis to underlying tissues.
Connective tissue layer.
Contains muscle fibers.
Nerve cell processes.
Dermal blood vessels supply nutrients to all skin cells.
Hair follicles, sweat and sebaceous glands.
Sensory receptors: Lamellated (Pacinian) corpuscles for pressure, Tactile (Meissner’s) corpuscles for light touch.
The dermis consists of 2 layers:
Papillary layer:
Superficial layer.
Areolar connective tissue.
Thinner of the 2 layers.
Location of dermal papillae.
Reticular layer:
Deeper layer.
Dense irregular connective tissue.
Thicker of 2 layers.
Accessory structures of the skin:
Hair follicles.
Nails.
Skin glands (sweat and sebaceous).
3 parts of a nail:
Nail plate: overlies nail bed.
Nail bed: surface of skin, under nail plate.
Lunula: most active growing region; pale, half-moon-shaped region at base of nail plate.
Sebaceous Skin Glands?
Holocrine glands.
Usually associated with hair follicles.
Produce sebum, which consists of fatty material and cellular debris.
Sebum keeps hair and skin soft and waterproof.
Excess sebum can result in acne.
Absent on palms and soles.
Skin Glands: Sweat Glands?
Sweat Glands:
Also called sudoriferous glands.
Widespread in skin.
Originate in deeper dermis or hypodermis as ball-shaped coils.
Eccrine (merocrine) glands:
Most numerous.
Respond to elevated body temperature.
Apocrine sweat glands:
Axillary and groin areas.
Secrete by exocytosis.
Respond to emotions, pain.
Ceruminous glands—ear wax
Mammary glands—milk
Functions of the skin:
Protective covering, barrier against harmful substances and microorganisms.
Prevents some water loss.
Contains sensory receptors.
Excretes some wastes.
Helps produce Vitamin D.
Helps regulate body temperature.
Methods of heat loss:
1.Radiation: Primary method, infrared heat rays escape.
2.Conduction: Heat moves from skin to cooler objects.
3.Convection: Heat loss into circulating air currents.
4.Evaporation: Sweat changes into a gas, carries heat away.
Body Temperature Regulation:
When body temperature rises:
Thermoreceptors signal hypothalamus.
Vasodilation of dermal blood vessels.
Sweat glands are activated.
When body temperature falls:
Thermoreceptors signal hypothalamus.
Vasoconstriction of dermal blood vessels.
Sweat glands are inactive.
Muscles contract involuntarily (shivering).
Fever:
*Set point is elevated by the immune system, to fight infection.
*Phagocytes release pyrogens in response to presence of bacteria, viruses; hypothalamus increases set point and raises body temperature.
*Elevated body temperature helps destroy pathogens.
Loss of ability of homeostatic temperature control mechanism to function in an extremely hot environment:
*Exposure to very high heat can overwhelm temperature control mechanisms, leading to hyperthermia.
*If body heat builds up faster than heat can be lost from body, body temperature will rise, even when set point is normal.
*Extreme vasodilation can collapse cardiovascular system; can be fatal.
Hyperthermia:
abnormally high body temperature
Can occur on hot, humid day, when sweat cannot evaporate.
When air temperature is high, radiation is less effective.
Body may gain heat from hotter air.
Skin becomes dry, person gets weak, dizzy, nauseous, with headache, rapid pulse.
Hypothermia:
abnormally low body temperature
Can result from prolonged exposure to cold, or illness.
Shivering is involuntary skeletal muscle contraction, caused by hypothalamus.
Progresses to confusion, lethargy, loss of reflexes and consciousness.
Without treatment, organs shut down.
Sensory receptors:
Pacinian for pressure
Meissner’s for light touch.
Oil gland is the?
sebaceous gland
