Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

127 Cards in this Set

  • Front
  • Back
What are the nine steps of Insulin production in Pancreatic Basal Cells
1)Glucose enters cell through the Glut-2 transporter and signals insulin to be sercereted and for Nucleus to begin protien synthesis
2)mRNA transcribed from insulin gene on DNA
3)mRNA leaves nucleus and attacks to a ribosome on the rough ER and is translated into a protein (insulin)
4)Insulin enters rough ER and is modified into glycoprotein
5)Insulin is enclosed in a membranous vesicle and transported to golgi apparatus
6)moves through golgi apparatus and recieves finishing touches & shipping info
7)secretory vesicle leave golgi apparatus --> PM
8)secretory vesicle fuses with membrane
9)insulion secreted by cell via exocytosis --> bloodstream
3 possible fates of glucose after it has entered cell
1) storage of glucose as glycogen (in muscle & liver cells)
2)Glucose enters glycolysis
3)storgae of glucose as fatty acid
Once glucose levels are low in blood, why can't the glucose diffuse out of the cell?
Because glucose is rapidly phosphorylated to Glucose-6-Phosphate and there is no transporter-so it is trapped in the cell
found on all cells in low levels
-responsible for the minimum of glucose ness. to keep cell alive. -Cellular repiration- Main transporter for red blood cells
found in Pancreatic Beta Cells, liver cells, small intestine epi cells
found in neurons (especially the brain)
Insulin dependent transporter- found in muscle (skeletal & cardiac?
what is homeostasis?
the tendency of a cell or organism to maintain an internal elquilibrium
homeostasis variable
factor being regulated or controlled in the body
define hyperglycemia
abnormally high blood pressure
define hypoglycemia
abnormally low blood glucose
Most common cause: over dose of insulin or hypoglycemic drugs.
Brain cells only burn insulin, too much insulin--> insulin shock
why does an uncontrolled diabetic have hyperglycemia?
because the insulin isn't working properly, therefore the blood glucose gets higher and higher and the pancreas crank out more insulin in response to the high blood glucose signal.
describe Type I Diabetes
Child-onset (insulin dependent diabetes)
-defeincy of insulin due to the destruction of pancreatic beta cells (autoimmune disease)
-controlled by insulin replacement therapy & diet
describe Type II Diabtetes
Insulin is present but doing it's job= insulin resistance
-insulin receptor is defective, Glut-2 arn't present and glucose does
Which is more prevalent? Type I or Type II
Type II, and it is increasing rapidly in the US because of obesity
describe a negatiove feedback mechanism
reduces the intesity of the original stimulus, causes variables toi change in the OPPOSITE direction of the initial change (back into the range)
describe a positive feedback mechinism
when variable is disturbed by stimulus, a "cascade" reinforces or exagerates the original variable in the same dircetion as the initial change. pushes variable away from orginal value, until stimulus ends
examples of positive feedback mechinism
bloodclotting, intesification of labor contractions, and milk production & letdown
examples of negative feedback mechinism
blood pressure, body temp (denaturation), blood glucose
what are the elements of a control system?
1)change in variable
2) receptor (senses chnage)--> signal
3)signal afferent pathway (towards)
4)control center (descion)
5)efferent pathway (away)
6) effector (makes change)
7)brings variable back into range
General form: C6H12o6
Glucose, galactose, and frutose
what is glycogen?
the storage form of glucose, not eaten
(stored in muscles & liver)
3 stages of metabolism
big molecules break down into smaller molecules & abosrbed (occurs G1 tract)
molecules are broken down for energy ATP
building up molecules into lipids, protiens & glycogen which are used either for structure or storage or cellular processes
What is the role of NAD and FAD in cellular respiration?
these are the coenzymes that accepts the H's (electrons) and carry them to the electron transport chain
(they drop of electrons & protons)
what is an oxidation reaction?
a couple reaction (donor & acceptor) redox reaction
what is oxidized & what is reduced?
glucose is oxidized & oxygen is reduced
what does dehydrogenases mean?
enzyme that catalyzes a chemical ractions and removes hydrogen atoms from the molecule
what are the three stages of Cellular Metabolism?
1) Glycolysis
2)Kreb's cycle
3)oxidative phosphorylation/ ETC
what vitamin is NAD based on?
what vitamin is FAD based on?
what is the difference betweensubstrate level phosphorylation & Oxidative phosphorylation
substrate phosphorylation occurs in Glycolysis & Kreb's cycle
Oxidative Phosphorylation happens in the mitochondrian
what processes do substrate level phosphorylation use to make ATP?
An enzyme transfers a high energy phosphate group from a substrate molecule directly to adp which makes ATP
Why can't glucose leave cell after it has enter glycolysis?
Once glucose neters the cell it is rapidly phosphorylyzed into Glucose-6-phosphate, which has no tranporter so it is stuck inside the cell
Where does Glycolysis occur?
is Glycolysis anaerobic or aerobic?
How does glucose enter the cell during Glycolysis?
Via facilitated diffusion on a GLUT-4 transporter
What are the inputs and outputs of Glycolysis?
Inputs= 2 ATP to run process
Outputs= 2 pyruvate, 2 NADH+H+ (electrons on carrier going to ETC)
How many Net ATP are there in Glycolysis?
2 ATP net (from substrate phosphorylate)
What is pyruvate?
pyruvic acid
How are the 2 pyruvate prepared for the Krebs cycle?
The intermediate Step: the 2 pyruvate enter the mitochondrial matrix and are converted to 2 Acetyl CoA
What are the inputs of the intermediate step?
Inputs=2 pyruvate, (coenzyme A is recycled & used over and over again) and 1 carbon atom from each pyruvate is harvested for its electrons
What are the outputs of the intermediate cycle?
Outputs= 2 Acetyl CoA (conenzyme A going to Krebs) & 2 NADH+H+ (electrons going to Krebs)
What is the bi product of the Intermediate step?
CO2 --> diffuses right out of cell by simple diffusion (down conc. gradient)
Where does the Kreb's Cycle occur?
in the mitochondrial matrix
what are in the inputs after 2 turns of the kreb's cycle?
Inputs= 2 Acetyle CoA (turns cycle once each)
2 carbons of acetyl CoA
What are the outputs of the Kreb's cycle after 2 turns?
Outputs= 6 NADH and 2 FADH sq. (electrons going to ETC) and 2 ATP from substrate phosphorylation
What it thre biproduct after 2 turns of the Krebs cycle?
CO2--> diffuses out of cell
Why is the Kreb's cycle considered aerobic even though it uses no Oxygen?
because the oxygen keeps it running, the krebs cycle will stop if oxidative phosphorylation isn't happening because the NAD/FAD pumps get backed up
why is the Krebs cycle called the citric acid cycle?
b/c it is the the first compund in the cycle
where does oxidative phosphorylation occur?
ETC~ outside the inner membrane
What is the firststep of the ETC?
The NADH+ and the FADH2 arrive from either
1) Glycolysis
2)INtermediate step
3)Kreb's cycle
and then they drop off their electrons & protons
What is the 2nd step of ETC?
electrons are passed from carrier to carrier along the cristae of the inner mitochondrial membrane (the ETC)
What is the 3rd step of the ETC?
The electrons fall down the stair case and energy is released that runs pumps
-the pumps pump H+ across the inner membrane space against the conc gradient (active transport)
What is the 4th step of the ETC?
There is now a high concentration of H+ in the space & the H= protons rush into the mitochondrial matrix down their concentration gradient
what is the 5th step of the ETC?
The H+ flow through ATOP synthase which phosphorylates ADP into ATP (oxidative Phosphorylaion)
What is the 6th step of the ETC?
The O2 grabs the electrons that come down staircase(ETC)
-The O2 is the final electron acceptor
What is the 7th step in the ETC?
The H= protons that came though ATP synthase join with the O2 and electrons to form water
What are the inputs of the electron transport chain?
-10 NADH+ and 2 FADH2 (from glycolysis, intermediate step, & krebs)
What are the outputs of ETC?
34 ATP
What is the byproduct of ETC?
What is the approx. total of ATP made from one glucose molecule?
38 ATP
What happens to teh pyruvate if there is not enough oxgen in the for the Krebs cycle and the ETC to keep up with pyruvate being made?
the Pyruvate becomes lactic acid and enters the blood stream
-causes achy muscles and fatigue
What besides glucose can be burned during via catabolism?
Fats & amino acids
What is the enrgy density of CArbohydrates compared with fats?
carbohydrates have a higher energy density than fats b/c they can be broken down easily into ATP
What are two rules about glucose?
1) glucose must always be present in order to burn other fuel
2)The brain can ONLY burn glucose
When can glucose be created from amino acids?
When the body is in urgent need of energy...IE the body has been fasting ~ this is a last resort
Define chromosome
one coiled DNA double helix strands & histones
-one specific group of genes
define gene
a segment of DNA that codes for one protien or 1 polypeptde chain
define DNA replication
happens in teh S subphase of interphase
sister chromatid
an exact copy of chromosome that occurs during DNA replication
all cells in body except for gametes =46 chromosomes (2n)
# of chromosomes in gametes = 23 (n)
-# of chromosomes fRom each parent
sex cells :sperm & ova
-have haploid #
characteristics : eye color, hair color...
define locus
position on chromosome where a gene is found
homologous chromosome
the pair of chromosomes (one from dad & one from mom) that are the same length and code for the exact same traits (each in the same position or locus on the chromosome)
the non-sex chromosomes (all of the chromosomes except X & Y)
sex chromosomes
the 23rd pair of chromosomes.. femals XX, males XY the sperm cell determines the sex of the zygote....Y is much smaller than the X
a photomicrograph of the complete set of chromosomes of a single cell---shows number, size & shape of each chromosome
define allele
One of the alternative forms of a gene
-some gens have many different normal alleles & abnormal alleles
how many alleles in each individual?
2, one from mom & one from dad
- two alleles for a gene may code for the same trait or different forms of the trait (curly hair & straight hair)
dominant allele
the allele of a gene that is expressed even if only one copy of it is present
recessive allele
two copies of the recessive must be shown for the trait to show itself
an indivudual who has two identical alleles of a gene, one inherited from each parent
EX: dominant or recessive CC or cc
an individual who has two different alleles of a gene, one inherited from each parent
EX: Cc
the actual pairs present for a particular gene in an individual
the expression that results from these 2 alleles~ what you end up with
EX:straight hair
Female vs Male genome
the complete set of chromsomes from each parent~ mom and dad have different sex cells
-haploid ~ 2n
fertalized ovum
nuclear fertilization
when the nucleus of the sperm comes into contact with the nucleus of the ovum~ fertilizion= zygote
what happens in Interphase of Meiosis I?
during the S sub phase of interphase, every chromosome replicates into 2 sister chromatids attached by a centomere (still chromatin: 92 chromatids & 46 chromosomes)
what happens in prophase I of meiosis?
1) chromosomes condense & coil
2) homologous chromosomes seek eachother out ~join as tetrad
3)synapsis:H. chromosomes lay over eachother & button together @ chiasma
4)chromatids experience cross over of some genes(no longer eact copies)
5)nucler envelope breaks down
6) mitotic spindle forms and grabs kinetochores @ centromeres
7) tetraads begin moving to the center of the cell
What happens during metaphase I of meiosis I?
Tetrads line up equator & mom/dad chromosomes @ eitehr side of equator--> random allignment
Anaphase I of meiosis I
H. chromosomes are pulled apart and moved to opposite poles
What happens during Telophase & Cytokenesis of meiosis I?
the cell splits into 2, two daughter cells with 23 chromosomes in each cell (haploid cells)
-nuclear envelope reforms
-the chromosomes in the 2 daughter cells are mixed up as to wether they came form mom or dad
how many replicated chromosomes are their in each daughter cell from meiosis I?
23 chromosomes, 2 sister chromatids each
What happens in meisos II?
The 2 sister chromatids are pulled apart, they are eactly alike except for the cross over
-at the end of meiosis their is a total of 4 daughter cells, each with 23 chromATIDS IN EACH CELL
Why are all 4 daughter cells different?
because of random allignment & crossover
no diversity=all cells alike
when does spermatogenesis begin?
@ puberty
how many spermatzoa are created from one germ cell?
4 spermatazoa
when are the oocytes made?
before birth
When is meiosis I completed for oogenesis?
at puberty
how many ovum are created from one germ cell?
1 ovum
what is a carrier?
a carrier is the hetrozygous trait ~ lower case
-only offspring with aa have disease
hereditary: carrier traits: albinism, deafness, sickle cell
Multiple alleles for a gene
most genes have anumber of possible alleles
EXAMPLE: blood types
ABO blood types
what is polygenic inheritance?
many traits take a combinations of genes to make the trait
Example: skin color, height
what is sex linked inheritance?
expressed more in males b/c they don;t have a corresponding gene to dominate or mask the gene on Y chromosome
EX: hemophilia & color blindness
What are the 3 sources of genetic variation in humans?
1) Cross over
2)Random ALignment
3)Random fertilization
where in meiosis does crossover occur?
IN prophase I
chromatids lay ontop of each other & exchange alleles~ 1-3 cross overs per tetrad
@ end of meiosis called recombinant chromosomes
where in meiosis does random allinment occur?
metaphase I
what is random allignment?
mom or dad line up randomly opposing eacther on either side of equator
Where does random fertilization occur?
during fertilization if egg and sperm
what is random fertilization
which sperm makes it to which oocyte ~Totally random
between random fertlization & random allignment how many possible combinations are there?
over 72 trillion possible
what is the 4 souce of genetic variation?
-ultimatly cause genetic diversity
-extra chromosomes
-extra chromosomes in zygotes will not survive
-exception=sex cells
EXAMPLE down syndrome
once insulin has entered the blood stream, describe what happens after the insulin binds to the receptors on target cells
the cytoplasmic side of the recpetor phosphorylates itslef (target tissues = muscle & adipose)
what type of transport does glucose enter the cell?
facilitated diffusion
what happens to the transporters once the blood levels of glucose have declined?
The GLUT-4 transporters are edocytosed back into the cytoplasm to wait in their vesicles for next round
what are the two hormones involved in homeostatic mechanism?
Glucagon & Insulin
where is Insulin produced?
Pancreatic Beta cells
where is glucogon produced?
pancreatic alpha cells