Exam 1 Content - QP

system

a group of organs with a well-defined function in the body

physiology

the study of normal functions in the human body

reductionism

the idea that a system can be explained by its parts

holism

the idea that a whole system is greater than the sum of its parts due to emergent properties that arise from the interaction of the parts

nervous/endocrine system

regulates sensory input and integration; command and control

musculoskeletal system

regulates support and movement

cardiovascular system

regulates transportation between tissues and environmental interfaces

gastrointestinal system

regulates the digestion of food and adsorption of nutrients

respiratory system

regulates the blood gases and the exchange of gases with the air

renal system

regulates the volume and composition of bodily fluids

integumentary system

protects the body from microbial invasions; serves as a water vapor barrier; provides temperature control; the skin

reproductive system

passes life to the next generation

immune system

removes microbes and other foreign materials

teleology

the study of answers that reference a final cause

mechanism

a sequence of events that links the initial causal input that produces an effect that serves as the cause of the next event

vitalism

the idea that living things are not purely mechanistic and there is a higher organizing force

cell

the microscopic unit of life that is enclosed by a cell or plasma membrane

cell theory

1. All biological organisms are made of cells

2. Cells are the unit of life

3. All life comes from preexisting life

homeostasis

the maintenence of a constant internal environment

evolution

the slow formation of a new species

robust system

a system that functions even when faced with challenges

exteroreceptors

part of a sensory apparatus that senses the external environment

interoreceptors

part of a sensory apparatus that senses the internal environment

negative feedback loop

a control system commonly used by the body; where a sensor for a particular parameter monitors the level of the parameter, engaging a comparator in a actuator/effector response to correct the parameter value if it deviates from its set value

positive feedback control

a less common type of control system that reacts to the initial disturbance in the same direction; eventually returns the system to its baseline; blood clotting, parts of menstruation, parts of action potential, parturition

microbiota

the aggregate of bacteria in the body; engage in signaling systems making it a part of physiology

model

something used to understand and predict systems

Robert Hooke

a scientist in the 17th century examining a cork under a microscope, calling the compartments he visualized “cells”

human internal environment

comprised of plasma and interstitial fluids

anticipatory control

when a system prepares for a disturbance before it happens

threshold mechanism

mechanisms to regulate episodic or cyclical events

blood pressure

an example of a negative feedback loop where baroreceptors in blood vessels sense blood pressure, the brain compares the value to the set point, and if blood pressure is too high heart rate is decreased to dilate blood vessels, and if blood pressure is too low heart rate is increased to constrict blood vessels

catalysis

changing one metabolite to another to synthesize cellular constituents, degrade them, or provide energy

transport

moving things from outside to inside of the cell or from one cellular compartment to another

signal transduction

mechanisms to respond to chemical or electrical signals from other cells or within a cell

recognition

recognizing where to attach to other cells and extracellular structures

movement

moving to the proper position in the cellular matrix

control

participating in coordinated activities and selecting the parts of the genome to use

differentiation

the process of forming specialized cells for specific tasks

proliferation

the making of new cells; cell division and its control

organelles

structures in cells for specific functions

plasma membrane

the lipid bilayer separating the inside from the outside of the cell; determines what enters and exits the cells and participates in signal transduction and cell recognition

cytosol

the gel-like fluid that is part of the cytoplasm; where soluble biochemicals diffuse; where other organelles are suspended

cytoskeleton

comprised of microtubules, actin filaments, intermediate filaments and myosin filaments that aide in support, cell movement, and cell attachment

nucleus

the largest organelle of the cell that contains most of the cell’s DNA; organizes and controls cell differentiation

free ribosomes

organelles made of a 40S and 60S subunit that synthesize proteins

rough ER

part of the ER covered in ribosomes where membrane and secreted proteins are made

smooth ER

where lipids and steroids are synthesized

Golgi apparatus

where proteins go to be processed to specific locations

mitochondria

the main site of ATP synthesis; where oxidation and energy transfer occur

lysosomes

where worn-out organelles are degraded with hydrolytic enzymes

proteasomes

organelles that degrade tagged proteins

peroxisomes

where fatty acids are oxidized and foreign chemicals are detoxified

passive transport

requires no metabolic energy, includes diffusion and water-like channels that span the cell membrane

active transport

requires metabolic energy; primary directly couples energy to the transport of materials and secondary indirectly links energy to transport of materials

exocytosis

when vesicles fuse and secrete materials in extracellular space

endocytosis

when vesicles fuse and secrete materials inside the cell

pinocytosis

endocytosis of fluid

phagocytosis

endocytosis of particulate matter

cytoplasm

the fluid in the cell comprising the cytosol and the organelles

microtubules

hollow cylinders of tubulin that are the largest cytoskeletal filaments (~25 um diameter), playing roles in forming cilia and separating chromosomes in cell division

formed of alpha and beta subunits that form dimers and spiral into the hollow cylinder shape

are polar and have a negative and positive end, with the negative end anchored at the centrosomes (less change) and the positive end having fast dynamics (a lot of addition and removal

serve as a track for dyneine (travels in +) and kinesin (travels in -) to transport cargo

actin filaments

present in most cells but especially in muscle cells; is asymmetric in its interactions with myosin; determine the shape and movement of cell surfaces

has polarity ( + and - end), with most movement at the + end

help support cell surface, cell shape in microvilli, and allow muscle cells to contract

intermediate filaments

a diverse category of filaments made of elongated rod-like dimers; they have no polarity, can participate in dynamic subunit exchange, and do not bind a nucleotide

help in cell and organelle support and assist in cell adhesion

zonula occludens

tight junctions that join at one pole of the epithelium; they act as a barrier to stop free movement, fence to stop free migration of membrane components, and a signal to regulate proliferation, differentiation, and polarity

zonula adherens

a type of junction that is like a belt attachment that surrounds epithelial cells; joins actin bundles in adjacent cells

desmosomes

a type of junction joining intermediate filaments in adjacent cells; forms a “spot weld”

gap junction

a type of junction that joins cells with a watery channel which allows small ions to pass (carrying an electrical current)

lipids

a type of fatty molecules that are insoluble in water but are soluble in organic solvents

phospholipids

the type of lipid most abundant in membranes; are composed of a polar head, which is made of a glycerol attached to a phosphate which is attached to a polar head group, and two fatty acid tails attached to the glycerol

saturated fatty acids

when the carbons in the hydrocarbon chain are covalently bonded to four atoms (two hydrogens and two carbons)

unsaturated fatty acids

when the carbons in the hydrocarbon chain form at least one double bond; make membranes more fluid because their shape prevents tight packing

sphingolipids

a type of lipids that have a serine (not glycerol) backbone and are common in brain and nerve tissue

amphipathic

a type of molecule that has both a hydrophobic and hydrophilic region

surface tension

how much more water molecules at the surface are attracted to the bulk phase because of the increase in intermolecular forces

liposomes

hollow, spherical bilayers; recently used in therapeutics to carry drug cargo on the interior for cell uptake

peripheral proteins

membrane proteins that are loosely bound to the membrane

integral proteins

membrane proteins that are tightly bound to the membrane

transmembrane proteins

membrane proteins that span the width of the membrane; the sections that are exposed to the hydrophobic tails are made of hydrophobic amino acids

fluid mosaic model

the dynamic system where lipids for a plane that gradually curves around to form a closed surface

lipid rafts

microdomains of biological membranes that have different lipid to protein ratios than the rest of the membrane

caveolae

a type of lipid raft that forms indentations that flatten when stretched

clathrin

a lattice-like molecular structure with a curvature that aides in vesicles getting pinched off at the membrane

centrosome

the organelle that anchors microtubules

dynamic instability

the idea that microtubules are constantly changing, having high amounts of subunit exchange

inner mitochondrial membrane

where the electron transport chain is for converting energy to ATP

electrons are passed from donors to receptors, releasing energy

the energy creates a proton gradient across this membrane, with protons pushed into the intermembrane space

the protons move down their concentration gradient through ATP synthase

their movement spins a motor that generates energy to add a phosphate group to ADP to form ATP

endosymbiotic theory

the idea that mitochondria were originally their own cyanobacteria that were engulfed by a eukaryotic cell

mitochondria have a double membrane and have their own DNA and ribosomes

they are inherited in matrilineal fashion

carbohydrate coating

carbohydrate molecules on the exterior cell membrane; help immune cells recognize the body’s own cells

phosphatidic acid

the most simple phospholipid comprised of just the glycerol backbone and a phosphate group, along with the fatty acid tails

cholesterol

a rigid steroid molecule that make the membrane stiffer when incorporated by attracting the lipid tails to its rigid ring structure

scramblase

an enzyme that randomly flips lipids in the lipid bilayer membrane

flippase

an enzyme that is highly specific to certain types of lipids and moves them in one direction (typically inner —> outer)

are necessary because the membrane is asymmetrical, so this enzyme is needed to disproportionately direct lipids to one side of the membrane