Introduction to Physiology Flashcards
What physiological factors does the body maintain?
- pH level
- Temperature level
- O & CO2 level
- Blood pressure
- Intracellular and extracellular fluid volumes such as right amount of food intake
What is Physiology?
Study of how the body functions
What is a disease?
A failure to maintain homeostasis
What are the control systems of the body?
Nervous System & Endocrine System
What is a negative feedback mechanism?
- the most common feedback mechanism
- the output goes the opposite direction of the input
- eg. temp increases – body temp decreases
What is an Anticipatory Response?
- a type of NS/Endocrine Response
- a response that occurs prior to the evoking of the stimulus being presented
- it can be learned (eg. putting on a coat before stepping in the cold)
What is a feedback mechanism?
- A type of a NS/Endocrine Response
- a mechanism that respond to change in syste
What does a feedback mechanism consist of?
- set point = a range of values of a variable that do not bring about a response (normal range)
- receptors
- control areas
- effectors
What is a positive feedback mechanism?
- less common type of feedback mechanism
- the output intensifies the input (eg. uterine contractions during childbirth)
- therefore it is not homeostatic
What is the process of a feedback mechanism?
Variable –> receptors –> control area –> effector
What is a hypotonic solution?
When the ECF has lower OP (meaning lower solute & Higher H2O) than the ICF (cytosol), the water then moves in because water is lower inside.
- can result to cell swelling
What is a channel protein?
- A type of transport proteins
- form pores on membranes
- they can be gated or non-gated(leakage channel)
- selectively permits channel-mediated facilitated diffusion of water and specific ions
What is a carrier protein? Give an example
- a type of transport protein
- binds solute and carries it across the membrane
- allows protein carrier-mediated facilitated transport or active transport
- glucose transport
Difference between facilitated transport and active transport
Facilitated transport - goes along its concentration gradient (high to low) and requires no energy
Active transport - goes agains its concentration gradient (low to high) and requires energy
What are enzymes?
they control chemical reactions on outer and inner surface
eg. acetylcholinesterase (breaks down acetylcholine)
- Na+/K+ ATPase (pumps out NA+ and pumps in K+)
What are joining proteins?
- they anchor cell membrane to the cytoskeleton of an adjacent cell
- they form desmosomes, tight junctions and gap junctions in between cells
- extracellular fibres (usually glycoproteins
What is tonicity?
Response of a cell immersed in a solution
What is homeostasis?
The ability to maintain stable conditions in internal environments despite the changes in the external environments
What are membrane carbohydrates?
- they are usually glycoproteins or glycolipids
- it differs in every cell
- they allow cell to recognize type -eg. sperm recognizes egg
What is a solute?
the substance being dissolved
What is Phagocytosis?
- deals with the movement of large items into the cell such as bacteria
- also referred to as cell eating
What kind of layer does the cell membrane has?
- a phospholipid bilayer that accepts small molecules (O2 & CO2) and lipid soluble molecules and does not accept water soluble molecules
What is a solvent
the substance where the solute is being dissolved
What is facilitated diffusion?
- diffusions of ions through the membrane via channel proteins
What is the role of Osmosis in solute regulation
Solute concentration in body fluids must be maintained within narrow limits or cells will die
What is facilitated transport
- diffusion of large, charged or water soluble molecules across the membrane via specific carrier protein(molecules must bind to the protein to be transported
eg. glucose into liver or skel.muscle
What is osmosis?
- It’s a solvent movement
- The movement of H2O across a semipermeable due to H2O difference
- it goes through the pores(channels) or across the membrane bilayer
What is dilute solution?
High water concentration = low solute concentration
Solute depends on what?
number of ions or molecules NOT the type
Define osmotic pressure
pressure that needs to be applied to prevent a solvent of pure H2O (2) concentration from moving across a semipermeable membrane to another solution (S2)
What is a Secondary Active Transport?
- ## Instead of using ATP, it uses the concentration gradients Primary Active Transport has established.
What does Osmotic pressure measures?
- It measures the solute of a solution
- High solute = high OP
- Low solute = Low OP
If S2 (Solution 2) has higher salt concentration with a lower H2O, the osmotic pressure is?
Osmotic Pressure is higher
In a hypotonic solution, a cell can burst due to swelling. What is the term for this?
Lysis
What is hemolysis?
Burst of Red Blood Cells
What is a hypertonic solution?
- When the ECF has higher OP (meaning high solute & low H2O) than the ICF (cytosol).
- Water then moves out of the cell because of the lower H2O found outside
- this can cause shrinkage of the cell
What is an Isotonic solution?
When the ICF and ECF have the same OP
In RBC, all solutes equals within?
- 0.9% of a saline solution which is normal saline
What are the major body fluids?
Extracellular Fluids (ECF) & Intracellular Fluids (ICF)
What is a primary active transport? Give an example
uses ATP directly to transport molecules
- eg. Na+/K+ ATPase Pumps = Pumps out 3 Na+ and pumps in 2K+
An example of how a hypertonic solution can be used is:
Injecting 10% sucrose solution will move water to blood stream. This can be used to reduce brain edema (swelling)
What happens when body looses H2O such as sweating?
- blood goes up, OP blood goes up a well, which causes fluid from tissues to move into the blood.
- as a response, thirst will occur, and decrease of H2O renal loss which causes urine production
What is Pinocytosis?
- refers to cell drinking
- deals with fluids and dissolved substances
What is a vesicular transport?
- A type of active transport
- moves molecules via vesicles
What is a bulk flow?
movement of fluid and solutes together due to pressure gradient (high pressure to low pressure)
If Solution 1 and Solution 2 are both pure water, what is the state of osmotic pressure?
Osmotic pressure will not be required
What are receptor proteins?
Bind specific extracellular molecules called ligands
- eg. hormones and neurotransmitter
Organ systems functions to maintain homeostasis. True or False?
True
What is Exocytosis?
- A type of vesicular transport
- movement out of the cell
- vesicles contain hormones, neurotransmitter, enzymes etc.
- they fuse with cell membrane and release their contents to the ECF (this is triggered by the rise of cytosolic Ca2+)
What is a hydrostatic pressure?
The pressure that the fluid exerts on the wall or surface
Explain hydrostatic pressure in capillaries
- when the blood pressure is higher than ISF (osmotic pressure) then fluid will be pushed out of the capillaries
Give an example of a Secondary Active Transport
- With glucose, it uses Secondary Active Transport. The concentration gradient established by Primary Active Transport is used (high Na+ outside and low Na+ inside). The Na+ binds to the carrier protein with the glucose to enter the cell. The Na+, in this case is moving down its concentration gradient (high to low) while the glucose is going AGAINST its concentration gradient (low to high)
In which proteins, Active transport happens?
Carrier proteins
What is endocytosis and its two types?
- A type of vesicular transport
- It moves molecules into the cell
- Phagocytosis & Pinocytosis
What is a concentrated solution?
Low water concentration = high solute concentration
What do the body’s controls systems do?
Maintain homeostasis & permit departures from homeostasis in a CONTROLLED manner (eg. pregnancy, growth, sudden fright)
Give some examples of ECF
- blood plasma
- interstitial fluid (ISF)
What is an example of Identifying proteins?
- MHC = Major Histocompatibility Complex proteins
- it is present in all cells EXCEPT red blood cells
- it identifies cell as part of the body not foreign
What kind of proteins are present in the membrane of a cell?
- transport proteins
- receptor proteins
- enzymes
- joining proteins
- identifying proteins
What is simple diffusion?
diffusion of solutes through the bilayer membrane (O2, CO2 etc)
