Physiology Midterm Flashcards
4 Criteria for Anatomical Position
Body is erect facing forward with feet flat on the floor, arms at the sides palms & toes facing forward.
Sagittal Plane
divides body into right and left parts
Transverse Plane
divides body into upper and lower regions, also known as horizontal plane
Frontal Plane
divides the body into front and back portions, also know as coronal plane
Axial Skeleton
head, neck, trunk
Appendicular skeleton
limbs/ appendages
What are the organ systems of the body?
- integumentary
- skeletal
- muscular
- nervous
- endocrine
- cardiovascular
- lymphatic
- digestive
- respiratory
- urinary
- reproductive
Integumentary System
consists of skin & its derivatives–covers and protects the body
Skeletal System
bones, cartilage & ligament – forms framework of the body
Muscular System
muscles– provide movement and heat to the body
Nervous System
brain, spinal cord, nerves–receives and transmits stimuli and coordinates body activity
Endocrine System
ductless glands–regulates metabolic activities
Cardiovascular System
blood, heart, & blood vessels –transports substances throughout the body
Lymphatic System
lymph, lymphatic vessels, & lymphoid organs–major defense against disease
Digestive System
gastrointestinal tract & accessory organs–responsible for ingestion, digestion & absorption of food
Respiratory System
air passageways & lungs–responsible for the exchange of gasses between the external environment and the blood
Urinary System
kidneys, urinary bladder, and ducts,–eliminate metabolic waste from the body
Reproductive System
ovaries, testes and associated accessory organs– form new individuals for the continuation of species
Matter
anything that takes up space and has weight
Element
simplest form of matter
Atom
smallest unit of an element
Structure of an Atom
Protons–positive charge particles located in the nucleus, # of protons indicates what element that atom is, located in the nucleus, part of atomic weight
Neutrons-neutral particles in the nucleus of the atom, usually equal to the amount of protons, part of atomic weight
Electrons-negative charged particles, constant orbital motion around the nucleus
Isotope
a different number of neutrons in the nucleus, giving it a different atomic weight. Can create a radioactive isotope which has an unstable nucleus that decomposes to release energy or atomic particles
Ionic Bond
the attractive forces between cations and anions for form ionic compounds
covalent bond
result when atoms share electrons, they can share more than one pair of electrons, which can result in double or triple covalent bonds. Unequal sharing of electrons creates polar covalent bonds
Hydrogen bonds
intermolecular bond or attractions between molecules that are formed by the attraction between the electropositive hydrogen end of a polar covalent compound and the negative charges of other molecules or ions
synthesis reaction
chemical reaction form a complex molecule from two or more simple molecules
decomposition reaction
break down larger molecules into simpler ones
single replacement reaction
atom in a reactant is replaced by a different atom
double replacement reaction
involve the exchange of 2 or more elements to form new compounds
exergonic reactions
release energy
endergonic reaction
require energy–which is then stored in the chemical bonds
Mixture
2 or more substances that can be physically separated
Solutions
solute that is being dissolved and a solvent that does the dissolving
Suspensions
particles do not dissolve, they are suspended in the other molecules. in colloidal they remain suspended because the particles are so small, in a regular suspension the particles settle if left undisturbed
Acid
proton (hydrogen ion) donors
Bases
proton acceptors
Formation & Neutralization of Acids and Bases
Formation–electrolytes form positive and negative ions when they are dissolved in water
Neutralization– produce salts and water
Buffers
contain weak acid and a salt of that same acid, resist pH changes by neutralizing the effete of stronger acids and bases
what distinguishes living from nonliving
organization, metabolism, responsiveness, movement, reproduction
5 necessary factors for survival
- heat
- pressure
- water
- oxygen
- nutrients
Homeostasis
- constant internal environment
- lack can lead to illness or disease
- all systems in the body work together under the direction of nervous and endocrine system to maintain homeostasis.
- energy is necessary to maintain
Negative Feedback
homeostasis maintained by inhibiting changes, example body temp, blood sugar, blood pressure
Positive Feedback
homeostasis maintained by stimulating and causing a process or change at faster and faster rates, leading to a culminating event
cytoplasm
gel like substance in the cells, the medium where organelles fx, provides colloidal suspension
nucleus
- formed by nuclear membrane around a fluid nucleoplasm and is the control center
- threads of chromatin contain DNA
- nucleolus is dense region of RNA in nucleus which is the site of ribosome formation
mitochondria
energy production–synthesize ATP
ribosomes
granules of RNA that synthesize protein
smooth endoplasmic reticulum
series of membraneous channels that transports certain lipids–does not contain ribosomes
rough endoplasmic reticulum
contains ribosomes–transports proteins
golgi body
modifies substances that are produced in other parts of the cell and prepares them for secretion
lysosome
contain enzymes that break down substances taken in at the cell membrane and destroy cellular debris
Simple Diffusion
movement of particles from a region of higher concentration to a region of lower concentration; can take place through a permeable membrane
facilitated diffusion
requires a special crier molecule but still moves particles from higher to lower concentration
osmosis
diffusion of solvent/water molecules through a selectively permeable membrane; cells placed in hypotonic solution will take in water through osmosis and will swell due to the increase intracellular volume; cells pale in a hypertonic solution will lose fluid because of cosmos and will shrink.
filtration
uses pressure to push substances through a membrane; pores in the membrane filter determine site size of the particles that twill pass thought it.
active transport
move substance against a concentration gradient from a region of lower concentration to a region of higher concentration and require a crier molecule and cellular energy.
fx of hydrochloric acid
located in stomach along with digestive enzymes to continue to digest food that began in the mouth
*digest food chemically and protects the body by killing bacteria present in our food
fx of bile
emulsify large masses of lipids into tiny globules for easy digestions
fx of peristalsis
muscular wave that travels the length of the GI tray moving partially digested food a short distance down the tract
fx of segmentation
only occurs in small intestine, helps to increase the absorption of nutrients by mixing food and increasing its contact with the walls of the intestine
Urinary System Facts
kd, ureters, urinary bladder & urethra
- kd’s filter the blood to remove wastes and produce urine
- the rest act as plumbing system to drain urine from the kidneys, store it & release it during urination
- overall also maintains the homeostasis of water, ions, pH, blood pressure, calcium and red blood cells
Homeostasis–Ions
kidney control the excretion of potassium, sodium, calcium, magnesium, phosphate and chloride ions into urine.
- if they are too highly concentrated the kidneys can increase their excretion out of the body
- if they are too low in concentration the kidneys allow these ions to be reabsorbed into the blood during filtration
Homeostasis–pH
kidneys monitor and regulate the levels of hydrogen ions and bicarbonate ions in the blood to control pH
- H+ ions are created as a natural byproduct of metabolism of dietary proteins and accumulate in the blood over time
- kidneys excrete excess H+ ions into urine for elimination from the body
- they also conserve bicarbonate ions, which act as important pH buffers in the blood
Homeostasis–Osmolarity
cells of the body need to grow in an isotonic environment (balanced) in order to maintain fluid and electrolyte balance
- kd’s maintain this by controlling the amount of water that is filtered out of the blood and excreted into urine
- when a person consumes a large amount of water the id’s reduce their reabsorption of it to allow the excess water to be excreted in urine.
- when you are dehydrated your kd’s reabsorb as much water as possible back into the blood to produce highly concentrated urine full of wastes and ions
- controlled by the antidiuretic hormone (ADH) produced by the hypothalamus
homeostasis–blood pressure
kd’s monitor the body’s blood pressure,
- when it is elevated the id’s can help to reduce blood pressure by reducing the vole of blood in the body (by reducing the reabsorption of water into the blood and producing watery dilute urine)
- when its too low they produce an enzyme (renin) to constrict blood vessels and produce concentrated urine
homeostasis–filtration
nephrons in the kd are the fx’l unit that filters blood to produce urine
- arterioles in the kd deliver blood to a bundle of capillaries surrounded by a capsule called a glomerulus–blood flows though it under pressure and much of the blood’s plasma is pushed out of the capillaries and into the capsule
- this leaves the blood cells and a small amount of plasma to continue flowing through the capillaries
- liquid filtrate in the capsule flows though a series of tubules lined with filtering cells surround by capillaries
- cells around the tubules absorb needed water and substances and return it to the blood in capillaries and waste is secreted into filtrate
homeostasis–storage and excretion
after urine is produced by the kd’s, it is transported thought ureters to the urinary bladder, this fills and stores until body is ready for excretion, when volume reaches 150-400 milliliters which signals receptors that result in relation of the involuntary internal urethan sphincter and gives the sensation of needing to urinate.
Kidney’s and Hormone Production
CALCITRIOL–the active form of vitamin D produced by kd’s from precursor molecules produced by UV radiation striking skin. it works with parathyroid hormone to raise level of calcium in bloodstream. it promotes the small intestine to absorb calcium from food and absorb calcium from food and stimulates osteoclast to break down bone matrix to release calcium ions into blood.
ERYTHROPOIETIN- (epo) produced by kd’s to stimulate the production of red blood cells, if the blood is hypoxic (not enough oxygen) the cells will produce and release epo into blood stream and travel to red bone marrow where it stimulates an increase of rbc’s
RENIN-enzyme for blood pressure and blood volume
ANGIOTNSIN II- stimulates adrenal cortex to produce-
ALDOSTERONE-change fx to increase reabsorption of water and NA ion to increase bp and volume
Integumentary System Facts
skin, hair, nails and exocrine glands
- skin is a few millimeters thick, but largest organ of body
- average person’s skin weighs 10lbs & 20 sq ft surface area
- skin outer covering and barrier to protect body from chemicals, disease, UV light, and physical damage
- hair/nails-protect from environmental damage
- exocrine glands produce sweat, oil and wax to cool, protect and moisturize skin surface
Epidermis
most superficial layer of skin
-covers almost entire body’s surface
-1/10th of a millimeter thick
-made of 40 to 50 rows of stacked squamous epithelial cells
5 layers–stratum…basale, spinousum, granulosum, licidum, & corneum
-avascular (no blood or blood vessels)
-receive nutrients via diffusion from dermis
Keratinocytes
90% of epidermis cells
-develop from stem cells to produce and store keratin protein (very tough, scaly and water resistant)
Melanocytes
8% of epidermis cells
-produce melanin pigment which protects from UV radiation and sunburn
Langerhans Cells
just over 1% of epidermis cells
-detect and fight pathogens that attempt to enter skin
Merkel Cells
<1% of epidermis cells
-form a disk along the deepest edge of epidermis where they connect to nerve endings in the dermis to sense light touch
Dermis
deep layer of skin found under epidermis
- mostly dense irregular connective tissue, w/ nervous tissue, blood and blood vessels
- much thicker than epidermis–gives skin strength and elasticity
- papillary layer–borders epidermis and contains finger like papillae that protrude toward epidermis–increase surface area of dermis and contain many nerves and blood vessels, which provide nutrients and oxygen to epidermis, feel touch, px and temp
- reticular layer–deeper layer–thicker and tougher made of dense irreg. connective tissue that contains collagen and stretchy elation fibers and contains blood vessels to support the skin cells and nerve tissue to sense press and px in skin
hypodermis
deep to the dermis
- layer of loose connective tissues that are flexible connection between the skin and the underlying muscles and bones as well as fat storage area
- fatty adipose tissue stores energy here in form of triglycerides–helps insulate the body by trapping body heat produced but eh underlying muscles
Temp Homeostasis via the skin
controls how the body interacts with its environment
- hyperthermia–skin will reduce temp by sweating and vasodilatation-evaporation of sweat absorbs heat and cools the boy’s surface/muslce lining the blood vessels relax and allow more blood to enter the skin–blood transports heat through the body and pulls away froth body’s core to the skin where it can radiate out of the body
- hypothermia–skin will raise temp by contraction of arrestor pili muscle and vasoconstriction
Vitamin D Synthesis via the skin
produced by UVlight striking the skin and sterol molecule to convert into vitamin D3 which is converted in the kidney’s into calcitriol the active form of vitamin D.
Skin color
controlled by 3 pigments–melanin, carotene and hemoglobin
MELANIN-brown or black pigment produced by the melanocytes to protect the skin for uv radiation
CAROTENE-present in skin that produces yellow or orange cast to skin and most noticeable in people with low melanin levels
HEMOGLOBIN-red pigment found in red blood cells gives skin light red/pink color
Cutaneous Sensation
skin allows body to sense by picking up signals for touch, pressure, vibration, temp and px.
- merkel disks connect to nerve cells to detect shapes and textures of objects
- corpuscles of touch are found in dermal papillae that also detect touch by objects contacting skin
- lamellar corpuscles found deep in dermis sense pressure and vibration
- plus many free nerve endings in dermis that are sensitive to px, warmth or cold
- density of these receptors varies throughout the body resulting in certain areas being more sensitive than others
