Lecture 1 Flashcards
what are the levels of structural organization in the human body?
chemical level
cell
tissue
organ
system
organism
level defined at atoms and molecules in the body
chemical level
level defined as basic structural and functional units
cell
level defined as groups of cells arising from common ancestor cells that work together to perform a particular function
tissue
level defined as structure composed of two or more types of tissues that have specific functions
organ
level defined as several related organs that have a common function
system
level defined as all parts of the body functioning together with one another
organism
what is the basic living unit of the body?
cell
how many functions can a cell have?
one or more
what is the most abundant cell?
RBC or red blood cell
what are the shared characteristics of all cells?
- Have metabolism - use oxygen, carbs, fats, proteins to function
- use the same chemical mechanism for changing nutrients to energy
- release end products into surrounding fluid
- almost all reproduce
what are organelles?
the cell membrane limited structures that carry out cell function
what are all the flu9ids inside the cell called?
protoplasm
how much of protoplasm is water?
70%
what else other than water is the protoplasm made up of?
Nucleic acids, proteins, lipids, carbs
Ions (potassium, magnesium, phosphate,sulfate,bicarbonate, sodium, chloride, calcium) for cell reaction and control
what are the major divisions of protoplasm?
cytoplasm
Nucleoplasm
what is the cytoplasm
Part of protoplasm that is exclusive of the nucleus
what is the nucleoplasm
(karyolymph)
fluid of the nucleus in which chromatin, nucleolus, and other elements of the nucleus are suspended (occupying)
membrane bound structures
nucleus
mitochondria
endoplasmic reticulum
Golgi complex
lysosome
peroxisome
plasma membrane
structures that are not membrane bound
nucleolus
ribosomes
cytoskeleton proteins
structures involved in protein synthesis
nucleus
nucleolus
ribosomes
rough ER
structures involved in secretion
rough ER
Golgi aparatus
structures involved in metabolic reactions
mitochondria
peroxisomes
smooth ER
structures involved in digestion
lysosomes
structures involved in cytoskeleton
filaments
centrosome
cilia
flagella
what distinguishes eukaryotic cells from prokaryotic cells
nucleus
what is the control center and what does it consist of
nucleus
chromosomes
nucleolus
what is the site of ribosome synthesis
nucleolus
double membrane with 1000 pores that separate nucleus from the rest of the cell
nuclear membrane or envelope
what has a stress sensor which changes its shape
nucleolus
nucleolar enlargement and sources of stress
increased ribosomal activity
larger irregular shape
sources of stress include cardiac stress, some cold medicine
nucleolar disruption and sources of stress
shrinkage of nucleolus and unraveling of DNA
sources include hypoxia, DNA damage, genotoxic stress
site of protein synthesis and concentration of RNA
ribosomes
what do free ribosomes do?
make cytoskeletal and cytoplasmic proteins
- such as HgB found in cytosol
what do bound ribosomes do?
on rough ER
responsible for making the remaining membrane proteins
how do antibiotics like macrocodes, tetracyclines, and aminoglycosides work
inhibiting bacterial ribosomes
network of interconnected membranes that work together with the golgi aparatus
rough ER
what does the smooth ER do?
make steroid molecules
metabolize carbs
glycogen breakdown
detoxify drugs and poisons
where are smooth ER predominantly found?
liver cells “marker enzyme” - GLUCOSE 6 PHOSPHATE
striated muscle (cardiac and skeletal) “sarcoplasmic reticulum” stores Ca++ necessary for muscle contraction
membranous structure responsible for protein condensation and shipping secretory products like enzymes?
golgi aparatus
what do the golgi vesicles do?
bud off of GA
store enzymes in inactive state (proenzymes)
secrete them where they need to go and where they can be activated
what does the mitochondria do?
metabolic reaction like cellular respiration
breaks down glucose and fatty acids
makes ATP
Most of the ATP is formed in the mitochondria and then used for ?
membrane transport
protein synthesis
muscle contraction
what organelle have their own DNA and can replicate
mitochondria
mitochondrial DNA vs nuclear DNA
maternal and can mutate more frequently than nuclear DNA
What are marker enzymes
mark mitochondria for specificity
- succinate dehydrogenase (gastric or renal carcinomas)
- ATP synthetase
- Adenyl kinase
- creatine kinase
folds in mitochondria are called _____.
these folds contain ______.
Why are these important?
cristae
- large surface area for chemical reactions
oxidative enzymes
- cause oxidation which leads to ATP
What theory is there about peroxisomes?
may be formed by self replication or budding off ER
what are peroxisomes… their role?
vesicles with specific enzymes (oxidases)
detoxify ETOH, break down fatty acids in
and found in liver
peroxisome marker enzymes
catalase
urate oxidase
what medication increases # of peroxisomes to help lower lipid concentrations in the blood?
Clofibrate
syndrome when peroxisomes are absent
Zellweger’s syndrome (fatal)
lysosomes are synthesized in the ______ and processed in the _____.
They contain _______ enzymes.
rough ER
GA
hydrolytic enzymes (can split organic compound) that digest old cell parts, bacteria etc.
lysosomes marker enzymes
acid phosphatase
- digestive lipase converting lipids into fatty acids and glycerol
how does the lysosome avoid breaking down itself?
surrounding membrane keep enzymes inside so they do not damage the cell
lysosomal disorder
Tay Sachs disease
Tay Sachs disease
lipid digesting enzyme is missing
= increase in lipid [ ] = interfere with normal brain function
what is made up of protein subunits called filaments that maintain cell structure and permit cells to change shape and to move
cytoskeleton
three types of filaments that make up the cytoskeleton
microtubules
microfilaments
intermediate filaments
what do Microtubules move?
what are microtubule molecular motors?
move mitochondria, vesicles, and chromosomes from one area to another
kinesin and dynein
What do microfilaments move?
What are microfilaments molecular motors?
movement of the cell itself
linear movement
myosin (actin filaments role in muscle contraction)
what drugs can interfere with microtubule function?
paclitaxel
colchicine
vinblastine
centrosomes
contain centrioles
- proteins role in development of spindle fibers associated with cell division
when centrosomes duplicate and separate forming poles of miotic spindles (microtubules)
cilia and flagella
attach to the cell facilitating movement
flagella limited in numbers (sperm)
cilia large in number (mucokinesis in respiratory tract)
positive or negative movement of cells in response to release of chemical mediators
ameboid movement
ameboid movement is controlled by _______.
Example would be ______.
chemotaxis
white blood cells
movement controlled by ATP and adequate concentrations of magnesium and calcium
ciliary movement
example of ciliary movement
airways
fallopian tube
maintenance of nearly constant conditions in the internal environment
homeostasis
Important idea when it comes to homeostasis
keeping a steady state over a longer period of time (not minute to minute)
energy input = energy output
construction = destruction
condition in which contending forces are equal
and there is no net flow thru the system
equilibrium
NOT steady state
the body creates homeostasis within ________, _______, and _______.
normal [ ] of oxygen, carbon dioxide, glucose, hydrogen, potassium, calcium, and magnesium
normal osmotic pressure to reduce tendency of water to move
normal temperature
intracellular fluid
inside cell
primarily consists of K+, Mg2+, and phosphate ions
intracellular fluid
inside cell
primarily consists of K+, Mg2+, and phosphate ionse
extracellular fluid
space outside the cells
made up of primarily Na+ Cl- HCO3- O2 CO2 glucose, fatty acids, amino acids
extracellular fluid in humans comes from?
interstitial fluid 75-80%
plasma 15-20%
transcellular fluid 5%
feedback system components
- sensor
- control center
- transmission pathways
- effector (final result of a stimulus)
transmission pathways
afferent pathways
- incoming
efferent pathways
- outgoing
what measures the value of the variable to be regulated
sensor
what compares the input signal with some internal reference value
set point
reference value
compares the set value and the actual measured value (the difference between them)
comparator
produce some sort of output signal
signal pathway
brings the vital parameter closer to the set-point
effector
primary mechanism for maintaining homeostasis
negative feedback
(reverses or shuts of stimulus)
positive feedback
the result of the process amplifies the stimulus
