unit 1 exam phys Flashcards
this is founded directly beneath the dermis layer of the skin (hypodermis)
it is present around blood vessels, organs, mucous membranes, and in digestive and respiratory tracts
loose areolar tissue
what tissue stretches in multiple different directions. it is not strong, it provides support and cushions organs by holding them in place.
loose areolar tissue
anywhere with tubes is consideres which tissue?
loose areolar tissue
which tissue is strong, stretchy, made up of collagen and elastin fibers in random patterns?
dense irregular tissue
which tissue is founded where there’s tension from multiple directions?
dense irregular
found in dermis, submucosa of hollow organs, connective tissue sheaths of muscle and nerves
dense irregular
-cytes
cell
what are cells that create cartilage and only specialized in cartilage?
chondrocytes
what fills space between cells and fibers, primarily composed of water, large molecules like proteoglycans and glycosaminoglycans?
semisolid ground substance
what is found in most connective tissue: loose, cartilage, and bone?
semi-solid ground substance
what fills the space between cells and fibers in animal tissue?
ground substance
what is made up of large carbs, proteins (GAGs and proteoglycans)
ground substance
what is flexible and found in cartilage?
ground substance
2 components of ECM?
protein fibers (big) and ground substance
why do you want so many carbs?
to attract water
why does cartilage have a lot of ground substance?
its a shock absorber
what is the difference of ground substance for bones and cartilage?
it goes from semisolid to solid
cartilage in GS is made up of?
carb hyaluronan
bone in GS is made up of?
hydroxyapatite
what is cartilage connective tissue made up of?
chondrocytes
in cartilage connective tissue, what are chondrocytes surrounded by
semi-solid ground substance
what do bones store
calcium and phosphate
cells trap mineral salts, form calcifies ECM surrounding a canal of vessels and nerves. This is where?
bones
why do we need calcium
neurons and nervous system uses calcium
what happens if theres not enough calcium in our diet
weak bones because it keeps bones hard and strong. calcium is needed in the brain
whats phosphate used for
DNA and ATP production
what are composed of 2 or more tissues that serve different functions in the organ
organs
related organs working together to serve a common function
organ system
examples or organ system
digestive system, nervous system, reproductive system
how are organ systems built
tissues
how are tissues built
cells
how are cells built
stem cells
what are cells with potential to develeop into different types of cells in body
stem cells
what are the 2 main types of stem cells
embryonic and adult stem cells
what are the 3 embryonic germ layers
endoderm, mesoderm, ectoderm
connective and muscle tissue
endoderm
gives rise to all tissues (except nervous)
mesoderm
nervous tissue
ectoderm
what tissue is in all 3 germ layers
epithelium
categories of stem cells according to their potential and differentiate
totipotent
plutipotent
multipotent
oligopotent
unipotent
first embryonic cell. have potential to differentiate into any of the cells needed to enable an organism to grow and develop
totipotent
potential to differentiate into any human tissue but cant support the full development of an organism (form unrelated cells)
pluripotent
potential to differentiate into different types of cells within a given cell or lineage (RBC and WBC). restricted to 1 type of tissue type in adults
multipotent
example: bone marrow cells can become any type of blood cells
multipotent
limited to becoming one of a few different cell types
oligopotent
fully specialized and can only reproduce to generate more of its own specific cell type
unipotent
adult bone marrow has 3 types of stem cells:
hematopoietic
endothelial
mesenchymal
gives rise to RBC, WBC, and patelets
hematopoietic
gives rise to endothelium cell types that line blood and lymph vessels
endothelial
gives rise to muscle cells
mesenchymal
what is osteocytes function
regulate blood remodeling, maintain bone mass, regulate calcium and phosphate
what does it mean when zygotes are totipotent
their cells can become any cell
as cells differentiate…
a few adult stem cells are retained to allow for cell replacement
how many interrelated organ systems do humans have
11
what includes everything outside the cell
extracellular environment
where do cells recieve nourishment from and release wastes into
extracellular environment
cells communictae with each other by secreting ..
chemical regulators into the extracellular env.
does epithelium have a lot of ECM?
no
how do cells close to the surface get any nutrients if not alot of ecm?
diffusion thru spaces around the cell or surrounded fluid
example of chemical regulator
acetylcholine
why is acetylcholine a chemical regulator
it tells the next cell what to do
how does the next cell know to listen to a regulator
receptor binding sites. it has to have the right receptor to listen in the first place
what is the ecm of blood tissue and holds ecm fluid
blood plasma
what is blood plasma made up of
mostly waater. it is not clear because it has proteins, cell debree, ions, hormones
what do glycoproteins and proteoglycan have in common
both glycosylated proteins
what is ecm contained of
protein fibers of collagen and elastin, gel-like ground substance
what do protein fibers provide
structural support
what is ground substance composed of
glycoproteins and proteoglycans
what are made up of proteins and sugars, used right by the cells, interact with immediate env., and associate with itself
glycoproteins
what are glycoproteins that extend from the cell cytoskeleton and bind to ecm. interact with micro env.
integrins
what are Microtubules and Filaments. it is a structure that helps cells maintain their shape and internal organization, and it also provides mechanical support that enables cells to carry out essential functions like division and movement.
cytoskeleton
what are secreted and not bound to a cell
proteoglycans
what is the purpose of proteoglycans
to hold onto water which helps hormones diffuse
where do you find hematopoietic stem cells
cancellous bone, spongy bone, bone marrow
lacks oxygen
hypoxic
what is hypoxic
the environment arounnd the cell
functions include:
impart a polarity to cells
affect adhesion and motility
affect proliferation
functions of integrins
division no matter what it comes into contact with
proliferation
the distribution of charge, the relationship between opposing poles, or the presence of contrasting tendencies
polarity
is epithelium polar
yes! one side is tight junc while the other is adhearing
what is the plasma membrane made up of
phospholipid bilayer, glycoproteins, and channels
the plasma membrane is what kind of permeable
selectively- only allows some to pass
what are generally not permeable in the plasma membrane
proteins, nucleic acids, or other large molecules
what are generally permeable in the plasma membrane
ions, nutrients, wastes
can glucose get into the cell membrane
no, not by itself
how can glucose get into cell membrane
hormones cause target cells (because of right receptors) to put in a whole channel that lets glucose into cell. needs insulin to get glucose in
what can get through a phospholipid bilayer
water (slowly)
oxygen and CO2
what can get straight through phopholipid bilayer
hydrophobic (non-polar)
how does sodium get into cell
cell has to produce or change in some way so sodium can enter
proteins involved so it can happen in the first place, is considered which mediated
non carrier mediated
the channel to move water; proteins that act as water channels in cell membranes, allowing water to pass through cells
aquaporins
what limits what passes
size
specific to whats being transported
carrier mediated
what does not take apt to happen
diffusion
simple diffusion includes
water, oxygen, co2
what drives sodium in cell
molarity
uses atp to enable movement of molecule
transport
what drives sodium thru membrane
concentration gradient
what drives sodium in active transport
atp or pump
what systems primary function is protection and thermoregulation
integumentary
major organs of the integumentary system
skin, hair, nails
what systems primary function is regulation of other body systems
nervous system
what systems primary function is secretion of regulatory molecules called hormones
endocrine system
what are the major organs of the endocrine system
hormone-secreting glands such as the pituitary, thyroid, and adrenal glands
what systems primary function is movement and support
skeletal system
major organs of skeletal system
bones, cartilage
what systems primary function is movement of the skeleton
muscular system
major organs of muscular system
skeletal muscles
what systems primary function is movt of blood and lymph
circulatory system
what are major organs of circulatory system
heart, blood vessels, lymphatic vessels
what systems primary function is defense agaainst invading pathogens
immune system
major organs of immune system
red bone marrow, lymphoid organs
what systems primary function is gas exchange
respritory
what systems primary function is regulation of blood volume and composition
urinary
major organs of urinary system
kidneys, ureters, urethra
what systems primary function is breakdown of food into molecules that enter the body
alimentary
major organs of alimentary
mouth, stomach, intestines, liver, gallbladder, pancreas
what systems primary function is continuation of the human species
reproductive
major organs of reproductive
gonads, external genitalia, associated with glands and ducts
can glucose get into the cell membrane by itself?
No
how can glucose get into the cell memnbrane?
hormones cause target cells (because the right receptor) to put in a whole channel that lets glucose into the cell. it needs insulin to get in
which transport involves molecules to move from higher concentration to lower without the use of metabolic energy?
passive transport
what is a movement of substances across a membrane without cellular energy
passive transport
why is O2 and CO2 an example of passive transport
O2 diffuses into cells because more concentration outside of them, CO2 diffuses out of cell because more concentration inside. neither of these require energy; they use passive transport to move across memb
what is – molecules moving across cell membrane from the side where more concentration to the side with less
simple diffusion
which transport- molecules move from higher to lower concentration using ATP and specific carrier pumps
active transport
during this transport, atp is required to move a substance across a membrane, often with help of protein carriers and usually against its concentration gradient
active transport
what affect molecular movement and dictate the direction in which molecules will move.
concentration gradient
why is sodium potassium pump an example of active transport
it transports sodium out of cell while moving potassium into cell.
why are nerve cells abundant in sodium potassium pump
they constantly pump out sodium ions and pull in potassium ions to maintain electrical gradient
what consists of solvent and solute
solution
what is a solvent
water
what are molecules dissolved in water
solute
molecules in a solution are in a constant state of
motion
what will happen if there is a concentration difference between 2 regions
random motion will establish equilibrium via diffusion
what will occur without a physical separation or across a permeable membrane
diffusion
due to random movement, the net direction of diffusion is from high to low solute concentration
net diffusion
the average time it takes for a solute to diffuse
mean diffusion time
higher to lower concentration
net diffusion
equal concentrations
no net diffusion
what passes easily through lipid portion of membrane
small, nonpolar (or uncharged) lipid soluble ions
examples of small, nonpolar (uncharged) ions
oxygen, CO2, steroid hormones
what is gas exchange: net diffusion of O2 into cells and CO2 out of cells due to?
concentration gradient (opposite in lungs)
how can water diffuse using special channels
aquaporins and/ or passively
how can charged ions pass plasma membrane
they pass through ion channels that cross the plasma membrane that may always be open or gated
why cant larger polar molecules pass membrane
they cant pass through simple diffusion, they need special carrier proteins
what is measured by the number of diffusing particles per unit of time
rate of diffusion
rate of diffusion depends on
magnitude, permeability, temperature, and surface area
what is the driving force for diffusion- concentration difference
magnitude
The —of the osmotic gradient is proportional to the difference in the concentration of solutes on one side of the cell membrane to that on the other side.
magnitude
why can water move pass the membrane slowly, even though its polar
they do not carry a charge
where are many aquaporins found
kidneys, eyes, lungs, salivary glands, and brain
why does water move
wants to reach equilibrium
what creates channels in the membrane to aid diffusion of solvent
aquaporins
requirements of osmosis 1
there must be a solute concentration difference on either side of membrane permeable to water
requirements of osmosis 2
the membrane must be impermeable to the solute, or the concentration difference will not be maintained
what are solutes that cannot cross and permit osmosis
osmotically active
what can get into cell, does not cause osmosis, and permeable
osmotically inactive
what is the net movt of water
from the side with more water (more dilute) to the side with less water (less dilute)
what is the force surrounding a cell required to stop osmosis
osmotic pressure
what is the osmotic pressure of pure water
zero
a mole of a compound can be measured as its
molecular weight in grams
molecular weight of glucose
180g
moles solute/liter solution
molarity
moles solute/ liter solvent
molality
why can you compare solute concentrations to predict the direction of osmosis
amount of water never changes
what is the total molality of a solution when you combine all of the molecules within it
osmolality
what has an effect of a solute concentration on osmosis of water
tonicity
two solutions that have the same concentration of solutes (equal tension)
isotonic
all living cells in multicellular organisms have
a surrounding cell membrane
what is an extremely pliable structure composed primarily of back to back phospholipids (a bilayer)
cell membrane
what contributes to the fluidity of the embrane
cholesterol
in cholesterol, what is embedded within the membrane that have a variety of functions
proteins
a single phospholipid molecule has
phosphate group on one end called the head and 2 side by side chains of fatty acid that makes lipid tails
the phosphate group is negatively charged, making the head
polar and hydrophilic- water loving
attracted to water
hydrophilic
in what areas are phosphate heads attracted to water molecules
extracellular and intracellular environment
lipid tails are
uncharged and nonpolar(hydrophobic)- hates water
repels and repelled by water
hydrophobic
molecule is one that contains bioth a hydrophilic and hydrophobic reguion
amphipathic
how does soap work to remove oil and grease stains
because it has amphipathic properties
how does soap work by amphipathic properties
the hydrophilic portion can dissolve in water while the hydrophobic portion can trap grease in micelles that then can be washed away
because phosphate groups are polar annd hydrophilic, they are attracted to
water in the intracellular fluid
is the fluid interior of the cell
intracellular fluid
is the fluid env outside the enclosure of the cell membrane
extracellular fluid
the term given to extracellular fluid not contained within blood vessels
interstitial fluid
what forms the basis of the cell membrane
lipid bilayer, but peppered throughout with various proteins
what are the 2 types of proteins that are commonly associated with the cell membrane
integral and peripheral proteins
is a protein that is embedded in the membrane
integral protein
is an example of an integral protein that selectively allows particular materials, such as certain ions, to pass in or out of cell
channel proteins
is a type of recognition protein that can selectively bind a specific molecule outside the cell, and this binding induces chemical reaction within the cell
receptor
the specific molecule that binds to and activates a receptor
ligand
is a protein that has carb molecules attached, which extend to extracellular matrix
glycoproteins
is a fuzzy appearing coating around the cell formed from glycoproteins and other carbs attached to the cell membrane
glycocalyx
how are glycocalyx formed
carbs that extend from membrane proteins and even from some membrane lipids
an example of the role glycocalyx play
may have molecules that allow the cell to bind to another cell, it may contain receptors for hormones, or it may have enzymes to break down the nutrients
typically found in the inner or outer surface of lipid bilayer but can also be attached to the internal or external surface of integral protein
peripheral protein
what causes the membrane to be selectively permeable
The phospholipids are tightly packed together, and the membrane has a hydrophobic interior
what do some peripheral proteins on the surface of intestinal cells act as
they act as digestive enzymes to break down nutrients to size that can pass through the cell and into bloodstream
is difference in concentration across a space
concentration gradient
movt of particles from an area of higher to lower concentration
diffusion
three types of germ layers
ectoderm, mesoderm, endoderm
what gives rise to epidermis, glands on skin, some cranial bones, nervous system, and anus
ectoderm
(skin cells, neurons, pigment cells)
what gives rise to CTP, bones, cartilage, blood, muscles, kidneys
mesoderm
(cardiac muscle, skeletal muscle, RBC, smooth muscle)
what gives rise to lining of airways and digestive system except mouth and distal part of digestive system (rectum and anal canal); glands (digestive glands, exocrine glands, adrenal cortex)
endoderm
(lung cell, thyroid cell, pancreatic cell)
what aids diffusion of particles within the body
having an internal temp of 98.6deg F
what is the mechanism of molecules moving across a cell membrane from the side where they are more concentrated to the side where they are less concentrated? form of passive transport called
simple diffusion
what can not be easily cross the phospholipid bilayer
large polar or ionic molecules (hydrophilic)
why can very small polar molecules, such as water, cross via simple diffusion
due to their small size
why can charged ions or molecules of any size cannot cross the cell membrane via simple diffusion
the charges are repelled by hydrophobic tails inn the interior of the phospholipid bilayer
what is the diffusion process used for those substances that cannot cross the lipid bilayer due to their size, charge, polarity
facilitated diffusion
what is a common example of facillitated diffusion
movt of glucose into the cell, where its used to make atp
why cant glucose pass the lipid bilayer via simple diffusion
too large and polar
how can you get glucose to pass the lipid bilayer
a specialized carrier protein called the glucose transporter will transfer glucose molecules into the cell to facilitate its inward diffusion.
because facilitated diffusion is a passive process…
it does not require energy expenditure by the cell
how can Water move freely across the cell membrane of all cells
either through protein channels or by slipping between the lipid tails of the membrane itself.
what is osmosis
the diffusion of water through a semipermeable membrane
what happens If a membrane is permeable to water, though not to a solute
water will equalize its own concentration by diffusing to the side of lower water concentration (and thus the side of higher solute concentration).
Two solutions that have the same concentration of solutes are said to be —– (equal tension)
isotonic
When cells and their extracellular environments are isotonic…
the concentration of water molecules is the same outside and inside the cells, and the cells maintain their normal shape (and function).
when does osmosis occur?
when theres an imbalance of solutes outside of a cell vs. inside the cell
4 categories of tissues
epithelial, connective, muscle, and nervous.
what refers to the sheets of cells that cover exterior surfaces of the body, line internal cavities and passageways, and form certain glands.
epithelial tissue (epithelium)
what binds the cells and organs of the body together and functions in the protection, support, and integration of all parts of the body.
connective tissue
what is excitable, responding to stimulation and contracting to provide movement, and occurs as three major types: skeletal (voluntary) muscle, smooth muscle, and cardiac muscle in the heart.
muscle tissue
is also excitable, allowing the propagation of electrochemical signals in the form of nerve impulses that communicate between different regions of the body
nervous tissue
what is a single cell formed by the fushion of an egg and sperm
zygote (fertilized egg)
The first embryonic cells generated have the ability to differentiate into any type of cell in the body and, as such, are called
totipotent
— meaning each has the capacity to divide, differentiate, and develop into a new organism.
totipotent
germ layers and position
ectoderm (ecto- = “outer”), mesoderm (meso- = “middle”), and endoderm (endo- = “inner”).
in the germ layers, epithelial tissue are in all 3. nervous tissue derives primarly from the
ectoderm and muscle tissue from mesoderm
is a thin layer or sheet of cells that covers the outside of the body (for example, skin), the organs (for example, pericardium), internal passageways that lead to the exterior of the body (for example, mucosa of stomach), and the lining of the moveable joint cavities.
tissue membrane
2 basic types of membranes
conn tiss and epithelial membranes
what do conn tiss membranes include
synovial membranes
what do epithelial membranes include
mucous membranes, serous membranes, and the cutaneous membrane, in other words, the skin.
how are conn tiss membrane formed and encapsulate
formed solely from connective tissue. These membranes encapsulate organs, such as the kidneys, and line our movable joints.
what is a type of connective tissue membrane that lines the cavity of a freely movable joint.
synovial membrane
what does synovial membranes surround
the joints of the shoulder, elbow, and knee.
what do fibroblasts in the inner layer of synovial memb. release
hyaluronan into joint cavity
what effectively traps available water to form the synovial fluid, a natural lubricant that enables the bones of a joint to move freely against one another without much friction.
hyaluronan
what readily exchanges water and nutrients with blood, as do all body fluids.
synovial fluid
is composed of epithelium attached to a layer of connective tissue, for example, your skin.
epithelial membrane
is also a composite of connective and epithelial tissues. Sometimes called mucosae, these epithelial membranes line the body cavities and hollow passageways that open to the external environment, and include the digestive, respiratory, excretory, and reproductive tracts.
mucous membrane
what produced by the epithelial exocrine glands, covers the epithelial layer.
mucus
what is The underlying connective tissue (literally “own layer”), help support the fragile epithelial layer.
lamina propria
is an epithelial membrane composed of mesodermally derived epithelium called the mesothelium that is supported by connective tissue.
serous membrane
The skin is an epithelial membrane also called the
cutaneous membrane
what type of membrane resting on top of connective tissue.
stratified squamous
is the workhorse of the system, where the majority of digestion occurs, and where most of the released nutrients are absorbed into the blood or lymph,
small intestine
what organs play integral roles in the life-sustaining process of digestion.
all digestive organs
what does not work in isolation; it functions cooperatively with the other systems of the body.
digestive system
2 categories of digestive system
alimentary canal, accessory digestove organs
also called the GI, The main function is to nourish the body.
alimentary canal
where does the alimentary canal begin and end
mouth and ends at anus
what aids the breakdown of food
accessory digestive organ
4 tissue layers of alimentary tract
mucosa, submucosa, muscularis, and serosa
is referred to as a mucous membrane, because mucus production is a characteristic feature of gut epithelium.
mucosa
membrane consists of —, which is in direct contact with ingested food
epithelium
a layer of connective tissue analogous to the dermis.
lamina propria
the mucosa has a thin, smooth muscle layer, called
muscularis mucosae
In the mouth, pharynx, esophagus, and anal canal, the —is primarily a non-keratinized, stratified squamous epithelium.
epithelium
what kind of epithelium is in the stomach and intestines
simple columnar epithelium.
contains numerous blood and lymphatic vessels that transport nutrients absorbed through the alimentary canal to other parts of the body.
lamina propria
also serves an immune function by housing clusters of lymphocytes, making up the mucosa-associated lymphoid tissue (MALT).
lamina propria
thin layer of smooth muscle is in a constant state of tension, pulling the mucosa of the stomach and small intestine into undulating folds
muscularis mucosae
lies immediately beneath the mucosa
submucosa
A broad layer of dense connective tissue, it connects the overlying mucosa to the underlying muscularis
submucosa
what includes blood and lymphatic vessels (which transport absorbed nutrients), and a scattering of submucosal glands that release digestive secretions
submucosa
third layer of the alimentary canal
muscularis (muscularis externa)
what is muscularis in the small intestine is made up of
double layer of smooth muscle: an inner circular layer and an outer longitudinal layer.
what is In the most proximal and distal regions of the alimentary canal, including the mouth, pharynx, anterior part of the esophagus, and external anal sphincter
muscularis
is made up of skeletal muscle, which gives you voluntary control over swallowing and defecation.
muscularis
is the portion of the alimentary canal superficial to the muscularis.
serosa
what is present in the region of the alimentary canal within the abdominal cavity
serosa
what consists of a layer of visceral peritoneum overlaying a layer of loose conn tiss
serosa
the mouth, pharynx, and esophogus have a dense sheath of collagen fibers called
adventitia
these tissues serve to hold the alimentary canal in place near the ventral surface of the vertebral column
adventitia
what happens once food enters the mouth
it is detected by receptors that send impulses along the sensory neurons of cranial nerves
what does not require specific protein
non-carrier mediated
what is diffision based, concentration based, not require atp
non-carrier mediated
what involves facillitated diff and active transport
carrier mediated
what is specific and only wants certain molecules, but does not require atp
facillitated diff
what goes from low to high concentration and requires energy
active transport
what does active transport and facillitated diffusion have in common
goes from low to high conc
2nd law thermo
example of something that uses pumps (atp)
proteins in membrane of cell
what are electrons speaded equally around molecule and no specific sides
nonpolar
why can small nonpolar molecules go through the membrane
similar in chemical property to the hydrocarbon tails to inner core of phospholipid bilayer
hydrocarbon tails are polar or nonpolar
nonpolar
why can water still go thru membrane
its small
what do I use if I want water to move more quickly
aquaporins (water specific channel)
is the diffusion process used for those substances that cannot cross the lipid bilayer due to their size, charge, and/or polarity
facillitated diffusion
what works the universe in chaos, molecules diffuse to chaotic (equilibrium), and drives diffusion of solute
2nd law thermo
what are obstacles we have to overcome to transport using atp (rule tiny interactions)
2nd law thermo
what do some epithelium cells have to increase their surface area
microvilli, size of membrane
what explains the passing thru membrane, but some are quicker (dynamic) and the amount of SA they have to move in cell
mean diffusion time
membranes are highly
mobile/ dynamic
example of steroid hormone
cholesterol
testosterone nad estrogen are based of —- so they can move straight through membrane
cholesterol
why cant sodium move thru membrane by itself
full charge, not compatible with nonpolar lipid memb
how do you get sodium in cell
need protein structure to put in channel. Open the gate
what needs facilitated or active transport to get in cell
large polar molecules
example of large polar molecule
sugar
why do sugars hold water
sugars are polar. polar substances love each other
which channel has two states and not specific
non-carrier mediated
what would happen if the diffusion rate of sodium if the concentration in ECM was sharply increased
increase because bigger driving force
why does water move
to reach equilibrium
what describes osmotic pressure; describes 2 containers relative to each other
tone
what describes solute; describes that solute causes osmosis to happen
osmotically active
the only reason solute causes osmosis is if
solute cant move thru memb
what does not cause osmosis, but has some way to get into cell (some channels)
osmotically inactive
what are poles of solute have on water (power behind movt); pressure needed to stop
osmotic pressure
what happens when you put a cell in a hypotonic solution
water goes in cell; cells conc is high which makes cells hypertonic
cells cant avoid diffusion of water, net equilibrium, cells swell and result in
lyse/ burst
why do RBC have biconcave shape
increase in surface area relative to hemoglobin so it can transport more oxygen
hypertonic
water out/ shrink
isotonic
equal
hypotonic
water in/ swell and burst
what is a fixed number of particles per element, relate variable atoms to grams
moles
what is the purpose of avogadros number
gets is to concentrations
why are concentrations so important
because every solution has a concentration
1M/1L
1molar
moles solute/ liter solution
molarity
amount of moles of a compound dissolved in an amount of solvent (usually water)
molarity
for this example, i will take 58.6g NaCl and put in a dry beaker and add water until i get 1L solution
molarity
this cares about all particles.
most often used
take your molecular weight and add 1 liter of water
molality
why is molarity not useful when discussing osmosis
the solute concentration is different depending on the solute. 1M solutions differing solutes contain different amount of water
moles solute/ liter solvent
molality
1 — solutions take the molecular weight in grams dissolved in exactly 1L water
molality
what depends on how many particles are present in a solution
molality
in molality, how can you compare solute concentrations to predict the direction of osmosis
the amount of water never changes
the total molality of a solution when you combine all of the molecules within it
osmolality
electrolytes that dissociate in water have to be assessed differenlty by using
osmosis
a 1m NaCl solution would actually be a 2 Osm solution because
the 1 mole of NaCl dissociates into 1 mole of Na and 1 mole of Cl
same osmolality and same osmotic pressure
iso osmotic
how is it possible for the .3m glucose and .15m NaCl to have the same osmotic pressure
the NaCl splits into two seperate entities
same osmotic pressure means —- movt of water
no net
what takes into account the permeability of the membrane to the solutes. If the solutes can cross the membrane, the — will change
tonicity
solutions with lower solute concentrations
hypotonic
solutions with higher solute concentration than the cell
hypertonic
why must constant osmolality be maintained
so neurons are not damaged
what do osmoreceptors in the hypothalamus detect and what does it trigger
increases in osmolality (due to dehydration). this triggers thirst and decreased excretion of water in urine
sensory cells that detect changes in osmotic pressure in the body. They are located in the hypothalamus and help maintain fluid balance
osmoreceptors
what happens with a lower plasma osmolality
osmoreceptors are not stimulated, so more water is excreted in urine
examples of molecules that are too large or polar and cannot diffuse across the membrane
amino acids, glucose, etc
what are within the plasma membrane that move molecules that are too large and polar across the memb
carrier proteins
characteristics of carrier mediated transports
-they are specific to given molecules (can let multiple in like pro and pot)
-saturation (# of carriers are limited. how long it takes to fill up and reach max)
-competition for similar carriers or molecules
transport rates increase with increased molecule concentration until saturation is met. this is the — where all carriers are in use
transport maximum
why does concentration of a solute matter
everything has to be homeostatic regulated
how does increasing concentration of solute effect transportation of solute? effect how it diffuses?
makes it faster for those that can already pass the membrane
powered by random movt of molecules, no atp used
facilitated diffusion
why does it matter that in facillitated diffusion, the net movt is high to low conc
to reach equilibrium
what does gradient mean
one side of the cell is different than the other
requires specific carrier- mediated proteins
facilitated diffusion
may always exist in the plasma membrane or be inserted when needed
transport proteins
GLUT
The GLUT carrier proteins involve the facilitated diffusion of glucose, which carries molecules from an area of higher to lower concentration without ATP. Energy is not required in facilitated diffusion because molecules move along a concentration gradient from high to low.
glut carriers are specific to
tissue types
sometimes molecules must be moved from an area of low concentration to an area of high concentration. requires ATP. often called pumps
active transport
2 types of active transport, both require atp, both push a molecule against conc. gradient
primary and secondary
occurs when the hydrolysis of atp is directly responsible for the carrier protein function
primary active transport
the transport protein is also an ATPase enzyme that will hydrolyze ATP, found in which transport
primary active
in primary active transport, how is pump activated
by phosphorylation using a Pi from ATP
same carrier that pushes solute against its gradient is the same one that uses atp itself.
take atp, rip it apart, harness energy and use energy to force a solute against its gradient, est gradient, or maintain
primary active
what is found in all body cells.
ATPase enzyme pumps 3 Na out and 2 K in cell
sodium phosphate pump
functions of sodium phosphate pump
-provide energy for coupled transport of other molecules
-produces electrochemical membrane potential in neuron and muscle cells
-maintain osmolality
what does nak pump maintain
low k inside, high out
low na outside, high inside
why do we need NaK pump to maintsin its concentration gradient
osmotic regulation, osmotic pressure, charge of cell (needed for body), creates conc grad
a type of active transport that moves two substances across a cell membrane simultaneously.
bring in different protein against gradient.
secondary active transpirt
coupled transport
also called coupled transport
secondary active transport
during secondary active transport, the energy needed to move molecules across their conc grad is aquired by moving – back into the cell
(during secondary active)
sodium
since sodium was originally pumped out of the cel using atp, this is considered
active trans
the other molecule is moved with
sodium. This is the common way to transport
glucose
symport
the other molecule is moved in the
opposite direction from sodium
antiport
the uphill extrusion of Ca2+ from a cell is an example of
antiport
transport across epithelial membranes
absorption, reabsorption, transcellular transport
transport of digestive products
across intestinal epithelium into the blood
absorption
transport of molecules out of
the urinary filtrate back into the blood
reabsorption
transcellular transport
movement
of molecules through the cytoplasm of the
epithelial cells
electricity in form of charge and physical chemical
electrochemical membrane
makes brain think, contraction of muscle, release of calcium from bone
potential to cause an outcome
electrochemical membrane potential
protein directly using atp
primary active transport
why does naK pump need to constantly go
use these concentration and let them go freely, then it needs to be reset
needs 2 carriers. atp is used, product is against conc gradient
secondary active transport
how does re absorption happen in the kidneys
glucose in the blood goes into the kidneys, then it is filtered out
which transport across the epithelial membranes occur when cells take something from apical domain and ship thru cell, then secrete at basal domain
transcellular transport
which transport across the epithelial membranes occur when it flow and moves between cells using no atp
paracellular transport
why dpes transcellular always require atp?
moving large molecules thru cell
what increases the surface area
microvilli
which seconndary active transport occurs when molecules move with sodium, common with glucose
symport
sodium pot. pump is which type of transport
primary active transport
large molecules such as proteins, hormones, and neurotransmitters are secreted via
exocytosis
what requires atp; involves fushion of a vesicle with the plasma membrane
exocytosis
movement of large molecules such as cholesterol into the cell requires
endocytosis
requires atp; usually a transport protein interacts with plasma membrane proetins to trigger —
endocytosis
3 types of endocytosis
phagocytosis, pinocytosis, receptor mediated
which endo. is when cells use water to bring in h20
pinocytosis
which endo. is when cells engulf another cell
phagocytosis
extracellular substances now in vesicle
endocytosis
secretion now in extracellular fluid
exocytosis
what establishes and maintains electrochemical pump (seperation of charges)
NaK pump
what causes potential to use charges for activity
seperation of charges
there is a difference of charge on each side of the plasma membrane due to
-Permeability of the membrane
-Action of Na + /K + pumps
-Negatively charged molecules inside the
cell
what is the difference in charges called in the membrane
potential difference
what makes the inside of the cell negative compared to the outside
the potential difference
the cell membrane is not fixed. how can it change
-incorporate new channels
-open gates (which influences permeabiloity)
how can the change of potential happen in a membrane and change of balance
opening the gate
why is the inside of cell negative
anions cant exit the cell
why does K+ accumulate at high concentrations in the cell
-NaK pump bring in K
-membrane is perm. to K
-negative anions in the cell attract cations outside of cell
-limited by strong conc grad
why is the memb permeable to k
there are leaky channels
pores that allow K to go in
leaky channels
what is the K+ conc inside and outside? what does this mean
150mM inside
5mM out
-this means that there are tons of K+ inside, not outside
even tho theres tons of K+ inside the cell, what causes the inferior of the cell to be more negative than outside
intracellular anions
what causes the outer leaflet to be positive
high extracellular Na
how can the potential diff be measured
voltage
Ek for k+
-90mV
Ena for Na+
+66mV
how to cells respond to stimuli
change in electric voltage
Because the membrane is so permeable to K + , this
difference is often maintained by
K + concentration
gradient
when would K+ reach equilibrium
with more K+ inside than outside
what does Ek of -90Mv mean
-the inside has a voltage
90mV lower than the outside
-This is the voltage needed to maintain
150 mM K + inside and 5mM K + outside
why is RMP negative (-70mV to -80mV)
because we have more K+ (permeable to K+)
The concentration of sodium of a normal cell
12mM inside and 145mM outside
To keep so much sodium out, the inside would
have to be
positive to repel the sodium ions.
The membrane potential of a
cell not producing any impulses
(resting) depends on
-Ratio of the concentrations of
each ion on either side of the
membrane
-Specific permeability to each ion
what ions contribute to the RPM and why
K + , Na + , Ca 2+ and Cl −
they are used to change cell. for example, used for muscle and neurons (why calcium homeostatis is imp)
how can you change memb permeability
open gate for Na
will change potential
what is the key to how neurons and other tissues work
RMP
what will change the resting potential
change in permeability and change in the concentration of any ion inside/ outside the cell
role of NaK pump
-acts to counter K+ leaking out
-2K in, 3Na out to maintain voltage diff
-keeps RPM and conc differences stable (aka the electrogenic effect)
cells communicate using chemical signals. what are they
gap junctions, paracrine signaling, synaptic signaling, endocrine signaling
allow adjacent cells to
pass ions and regulatory molecules
through a channel between the cells
-allow cytosol to flow from one cell to the next
gap junctions
where are gap juntions used
cardiac and smooth muscle
Cells within an
organ secrete molecules that diffuse
across the extracellular space to nearby
target cells; often called local signaling
(delta cells)
paracrine signaling
involves
neurons secreting
neurotransmitters across a
synapse to target cells
synaptic signaling
what are the 2 options target cells can do when it recieves signal from neuron
excite or inhibit
involves
glands that secrete hormones into
the bloodstream; these can reach
multiple target cells
endocrine signaling
always specific; location of these depend on what theyre recieving
receptor
A target cell receives a signal because it has
—- —specific to it on the plasma
membrane or inside the cell
receptor proteins
signal molecules such as steroid
hormones, thyroid hormone, and nitric oxide gas
can penetrate the plasma membrane and interact
with receptors inside the cell
nonpolar
signal molecules such as
epinephrine, acetylcholine, and insulin bind to
receptors on the plasma membrane
polar
Intermediaries called –are sent inside
the cell to affect change
second
messengers
cAMP
Cyclic adenosine monophosphate (cyclic AMP
or cAMP) is a common second messenger
how is cAMP a secondary messenger
takes our atp and converts it to AMP (change shape). cAMP now acts as a signal
how do you activate cAMP
-signaling mol binds to receptor
-this activates an enzyme that produces cAMP from ATP
-cAMP activates other enzymes
-cell activates change in response
a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior
Gproteins
Gproteins are made up of 3 subunits:
alpha, beta, gamma
what subunits are anchored to the cell memb and keep the G protein right next to the receptor
alpha and gamma
what happens when the alpha is bound to GDP ( when inactive)
the 3 subunits stay tgthr
what happens when a ligans binds to receptor
shape changes and allows Gprotein to release GDP and bind GTP instead
what happens when alpha is bound to GTP
alpha seperates, where it is free to interact with other proteins
