Med Phys Exam 1
In a nerve fiber, the potential difference required to stop further diffusion of potassium from across the membrane is what?
-90mV
What are some examples of how substances can cross a membrane?
-Diffusion -Ligand Gated-channels -Voltage gated channels -Active transport
What are the four basic tissue types?
-Epithelial -Connective -Muscular -Nervous
What are the three types of muscle tissue?
-Skeletal striated, voluntary -Cardiac striated, involuntary -Smooth non-striated, involuntary
What are cell membranes made of?
-fat, creating a lipid bilayer -protein -glycoproteins
What are some of the organs that get rid of metabolic waste products?
-lungs expel CO2 -Kidneys -GI tract
What is the sodium level ratio, outside versus inside of the cell?
142mEq/L to 10mEq/L
How many ATP are generated in glycolysis?
2 ATP
In order for the 2 pyruvates to enter the Kreb cycle they have to be converted into what?
2 Acetyl-CoAs
What is glucose broken down into?
2 pyruvic acids
How many hydrogens are released from the original molecule of glucose by the end of the kreb cycle?
24 (4 from glycolysis, 4 from production of Acetyl-CoA, 16 from Kreb cycle)
What else is released in the conversion of pyruvate to Acetyl-CoA?
2CO2 and 4 hydrogens. NO ATP is released.
How many sodiums does the Na+-K+ pump pump out of the cell?
3 Na+ out for every 2K+ in
How much ATP is generated during the ETC?
32 ATP
What is the normal Cardiac Output for an adult?
5L
What is a normal internal pH?
7.4
What is normal oxygen saturation of the blood?
97% or above
When the cell loses K+ to the outside of the cell, this creates?
A negative potential inside of the cell.
What is a redundant system and what is an example?
A redundant system is a system where one organ stops functioning another organ can take over. The lungs and kidneys are an example for acid base balance.
What proteins enable cells to perform endocytosis?
Actin, myosin, and clathrin
What substance is the energy substance of the cell?
Adenosine Triphosphate (ATP)
What hormone controls sodium and potassium ions and protein metabolism?
Adrenocortical hormones
What is ATP made of?
An adenine, a ribose, and 3 phosphates
In blood capillaries where does exchange of extracellular fluid occur?
Between the plasma portion of the blood and the interstitial fluid that fills the intercellular spaces
What does the parathyroid hormone regulate?
Bone calcium and phosphate
How does the body maintain homeostasis so well in hostile environments?
By feedback systems, such as our nervous system (sensory input, integrative (CNS), and motor output) and hormone system.
How is energy released from ATP?
By the removal of the phosphates. The last two phosphates are high energy bonds that release free energy, which allows the cells to function.
What body parts are responsible for detecting changes in blood pressure?
Carotid bodies in the carotid arteries have baroreceptors that are stimulated by stretching of the arterial wall. The kidney can also regulate blood pressure.
What are two examples of useful positive feedback systems?
Child labor, clotting factor cascade
What are three examples of extracellular matrix components?
Collagen, elastin, and proteoglycans produced by connect tissue cells.
These hydrogens combine with what to form what?
Combine with hydrogen carriers, NAD+ and FADH, and the enzyme, dehydrogenase.
What category of tissue does blood and plasma fall under?
Connective tissue
What would the pupils do in a rest and digest situation?
Constrict
What are the functions of epithelial cells?
Covers body surfaces including the outside of the body, line the GI tract, vessels (alveoli), and body cavities, and form glands.
What is the emergency fuel to make ATP?
Creatine phosphate (phosphocreatine)
Transcription
DNA to RNA using RNA polymerase.
What are the purposes of the Kreb Cycle?
Get rid of CO2 Produce NADH and FADH2 (oxidizers) Accept Pyruvate
The nervous system controls the motor and sensory activities of the body, what does the hormone system control for homeostasis?
Hormones control metabolic functions.
Of those 5L, how many liters does a patient have to lose to die due to positive feedback?
If a patient loses 1L they will live, if they lose 2L they will die because the heart will not be able to maintain a high enough pressure, becoming weak, and will not be able to pump blood throughout the body.
What does the body do to compensate for a build up of Lactic Acid?
Increase ventilation in order to blow off more CO2
Where does the CO2 in the blood come from?
It comes from glucose metabolism. Breaking down glucose into pyruvate into acetyl CoA into CO2 and H2O
What makes nervous tissue unique?
It has the ability to conduct electrical signals
Why is it important to have this difference in substance level inside vs outside of the cell?
It is important to have these differences to create a concentration gradient. This is especially important for cells that depend on electrical potentials such as nerve cells and muscle cells.
High creatinine levels in the blood can indicate?
Kidney issues
If pyruvate does not enter the kreb cycle, what is generated?
Lactate, through anaerobic glycolysis, which can be turned into lactic acid, or can turn back into pyruvate and enter the kreb cycle.
The heart likes to use what substance for energy?
Lactic Acid. It likes to convert lactic acid into pyruvate for entrance into the kreb cycle.
What are the two stages that extracellular fluid is transported in the body?
Movement of blood through the body in the blood vessels Movement of fluid between the blood capillaries and the intercellular spaces between the cells.
List some body systems that require energy from food to function:
Muscle activity Gland secretion Maintenance of membrane potential by nerves and muscle fibers Synthesis of substances in the cell, such as proteins Absorption of food from the GI tract
What can cause high Creatine kinase (CK) levels?
Muscle wasting and heart attack
What are the most important products of the Kreb Cycle?
NADH and FADH2
What type of feedback system tries to bring the body back to stability?
Negative feedback, which consists of a series of changes that return the factor toward a certain mean value, thus maintaining homeostasis.
What vitamins are NADH and FADH2 made from?
Niacin (B3) and riboflavin (B2)
Is sodium fat soluble?
No, sodium will need a concentration gradient and an open voltage gated channel in order to go in or out of a cell.
How many ATP is formed in the Kreb Cycle?
Not much, only 2 ATP
What are NADH and FADH2 considered?
Oxidizers
Rest and digest is what sector of the ANS?
Parasympathetic nervous system
What is the term for cell eating?
Phagocytosis used by macrophages and some white blood cells
What are the important lipids found in cells?
Phospholipids and Cholesterol, both are insoluble in water and are therefore used to form the cell membrane
What is the term for cell drinking?
Pinocytosis, which is the only way proteins can enter a cell
What type of feedback system intensifies instability?
Positive feedback system
The neuronal cell membrane is most permeable to what ion?
Potassium (K+)
The sodium potassium pump is an example of primary or secondary active transport?
Primary active transport
Define peripheral proteins:
Proteins that are attached only to one surface of the membrane. Function as enzymes or as controllers of transport
Define integral proteins:
Proteins that protrude all the way through the cell membrane. Allow water soluble ions through, and can be selective. Act as carriers, second messengers, and enzymes.
What would these body parts do in a fight or flight situation?
Pupils- dilate Lungs- relaxes airways Heart- increases heartbeat Stomach- inhibit digestion Bladder- relaxes
What is rigor mortis?
Rigor mortis is the inability of the body to make ATP.
What are the three major portions of the nervous system?
Sensory input, the CNS, and the motor output.
Is the concentration of sodium greater on the inside or the outside of the cell?
Sodium concentration is greater on the outside of the cell.
What are some important substances that have to be high in the ECF and low in the ICF?
Sodium, chloride, bicarbonate, oxygen, glucose, fatty acids, amino acids
What is the function of the ETC?
Split each hydrogen atom into a hydrogen ion and an electron Use the electrons to eventually combine dissolved oxygen of the fluids with water molecules to form hydroxyl ions. Then the hydrogen and hydroxyl ions combine to form water.
What are the common epithelial cell shapes?
Squamous - line blood and lymph vessels including alveoli Cuboidal- line glands, terminal bronchioles of lungs, and kidney tubules Columnar- line the uterus, stomach, intestines, gallbladder, bile ducts
What role does proteins play in a cell?
Structural role as in microtubules and cytoskeleton Functional role as in enzymes and muscle filaments
Fight or flight is what sector of the ANS?
Sympathetic nervous system
Where is the energy within the NADH and FADH2?
The electrons and hydrogens
What is osmolality?
The measure of one substance dissolved in another substance. The greater the number the substance that is dissolved the higher the osmolality.
Where does the electron transport chain take place in the cell?
The mitochondria
Where does the kreb cycle take place?
The mitochondrial matirx
Is there a higher concentration of K+ inside or outside the cell?
There is a higher concentration of K+ inside of the cell.
Build up of lactic acid in your muscles causes them to hurt because?
There is an decrease in blood pH in the muscles
Body temperature, pH, calcium, potassium, and sodium levels have what in common?
They all have a small deviation from their normal levels
What happens if an elderly patient drinks too much water?
They can become hyponatremic because if you drink too much water and your kidneys cannot handle the load, the extracellular fluid becomes diluted causing water to rush into the cells, bursting them.
What is the function of dehydrogenase?
To cause the release of CO2 from the substrate. The CO2 is then released into the blood, transported to the lungs, and expired from the body.
What is the energy used for from breaking the bonds of glucose, fats, and proteins?
To generate ATP
What are the functions of neuroglia?
To support, nourish, protect, and insulate the cell
What lipid is found in fat cells and used for energy?
Triglycerides
Are capillary walls permeable?
Yes to certain molecules
A concentration difference of ions across a selectively permeable membrane can produce what?
a membrane potential
Active transport can move a substance?
against an electrochemical gradient
What is the thyroid hormone responsible for regulating?
cell metabolism
Carbohydrates play what role in cells?
cell nutrition
Where does Glycolysis occur in the cells?
cytosol
Primary Active Transport
energy is derived directly from the breakdown of ATP
What happens to your heart rate if your body needs more oxygen?
increase
Is the autonomic nervous system voluntary or involuntary?
involuntary
What is the function of the Na+-K+ pump?
it is responsible for maintaining the sodium and potassium concentrations across the cell membrane, as well as establishing a negative electrical potential inside the cell.
There is what type of relationship between the amount of oxygen we consume to the amount of work done?
linear
Translation
mRNA and ribosome to make proteins by decoding codons
What are some important substances that have to be high in the ICF and low in the ECF?
potassium, magnesium, and phosphate
The potential difference between the inside and the outside of the cell is called?
the diffusion potential.
Secondary Active Transport
the energy is derived secondarily from energy that has been stored in the form of ionic concentration differences between the two sides of a membrane.