Anatomy & Physiology I FINAL EXAM REVIEW
homeostasis
the maintenance of relatively stable conditions in the body's internal environment. Occurs because of the ceaseless interplay of the body's many regulatory systems.
bulk-phase endocytosis
"Cell drinking"; movement of extracellular fluid into a cell by infolding of plasma membrane to form a vesicle; a form of endocytosis in which tiny droplets of extracellular fluid are taken up
phagocytosis
"cell eating"; a form of endocytosis in which the cell engulfs large solid particles, such as worn-out cells, whole bacteria, or viruses. Only a few body cells, termed phagocytes, are able to carry this out. Two main types of phagocytes are macrophages, located in many body tissues, and neutrophils, a type of white blood cell.
connective tissue
-Functions: protects and supports the body and its organs; Various types of these tissues bind organs together, support and strengthen tissues, store energy reserves as fat, compartmentalize and transport: i.e. blood, protect and insulate internal organs, and help provide the body with immunity to disease‐causing organisms. -Characteristics: vascular (cartilage is the exception), innervated: supplies organs with nerves, extracellular matrix (ground substance), cells.
what affects the chance that a collision will occur?
-the concentration of the reactants -temperature -the presence of a catalyst (enzyme)
characteristics of a living organism
6 important life processes: -metabolism -responsiveness -movement -growth -differentiation -reproduction
digitalis
A Na+/K+ pump inhibitor; Allows Na+ to accumulate within the heart muscle cells; Ultimately allows Ca++ to remain inside the cell as well and strengthens the force of the heart beat; Used to treat heart failure
ion channel (integral)
Allows specific ion to move through water-filled pore. Most plasma membranes include specific channels for several common ions.
diffusion
Both the solute and solvent diffuse across the cell membrane down their concentration gradient -a passive process
matter
Includes: -solids: have a definite shape and volume. Ex: teeth -liquids: have volume and assume the shape of their container. Ex: blood -gases: have neither a definite shape nor volume. Ex: oxygen * It's made up of elements
sodium-potassium pump
The most prevalent primary active transport mechanism expels sodium ions (Na+) from cells and brings potassium ions (K+) in. All cells have thousands of these pumps in their plasma membranes. -These pumps maintain a low concentration of Na+ in the cytosol by pumping these ions into the extracellular fluid against the Na+ concentration gradient. -At the same time, the pumps move K+ into cells against the K+ concentration gradient. -Because K+ and Na+ slowly leak back across the plasma membrane down their electrochemical gradients—through passive transport or secondary active transport—the ______ ________ pumps must work nonstop to maintain a low concentration of Na+ and a high concentration of K+ in the cytosol.
receptor
a body structure that monitors changes in a controlled condition and sends input (nerve impulses; chemical signals) to a control center. -this is an afferent pathway since the info flows toward the control center
effector
a body structure that receives output from a control center and produces a response/effect that changes the controlled condition. Ex: when body temp decreases sharply, your brain (control center) sends nerve impulses (output) to your skeletal muscles (effectors) and results in shivering, which generates heat and increases body temp
carrier-mediated facilitated diffusion
a carrier (also called a transporter) moves a solute down its concentration gradient across the plasma membrane -a passive process; no cellular energy is required -The solute binds to a specific carrier on one side of the membrane and is released on the other side after the carrier undergoes a change in shape. -The solute binds more often to the carrier on the side of the membrane with a higher concentration of solute. -Once the concentration is the same on both sides of the membrane, solute molecules bind to the carrier on the cytosolic side and move out to the extracellular fluid as rapidly as they bind to the carrier on the extracellular side and move into the cytosol. -How quickly this process occurs is determined by the steepness of the concentration gradient across the membrane. -Substances that move across the plasma membrane by carrier-mediated facilitated diffusion include glucose, fructose, galactose, and some vitamins.
facilitated diffusion
a substance moves across the lipid bilayer aided by a channel protein or a carrier protein; In this process, an integral membrane protein assists a specific substance across the membrane. The integral membrane protein can be either a membrane channel or a carrier. -Solutes that are too polar or highly charged to move through the lipid bilayer by simple diffusion can cross the plasma membrane by this passive process.
free radicals
an electrically charged oxygen atom with an unpaired electron; we produce them when we make energy; they cause damage: disorders and diseases are linked to them: cancer, atherosclerosis, Alzheimer disease, diabetes mellitus, rheumatoid arthritis, aging deterioration -formed by inflammation (obesity), UV light, metabolism, etc. -antioxidants is thought to slow the pace of damage caused by these.
growth
an increase in body size due to cell development and differentiation. Ex: in growing bone, mineral deposits accumulate between bone cells, causing the bone to grow in length and width.
atoms
an individual element; the building blocks of matter. Ex: an individual oxygen ______
catalysts
are chemical compounds that speed up chemical reactions by lowering the activation energy needed for a reaction to occur; most important are enzymes
enzymes
catalysts; speed up chemical reactions by properly orienting molecules to increase the frequency of collisions; lowers the energy required to start a reaction
enzyme (integral and peripheral)
catalyze reactions inside or outside the cell. Ex: lactase on the membrane of cells lining your small intestine break apart the chemical bonds of lactose in the milk you drink
the skeletal system
components: bones and joints and their associated cartilages. Functions include: -supporting and protecting the body -provides surface area for muscle attachments -aids movement -houses cells that produce blood cells -stores marrow, minerals, and lipids
cytoplasm
consists of all the cellular contents between the plasma membrane and the nucleus, and has two components: (1) the cytosol: fluid that surrounds the organelles and (2) organelles, tiny structures that perform different functions in the cell. -maintains cell shape
unsaturated fatty acids
contains one or more double covalent bonds between the carbon atoms of the hydrocarbon chain. Thus, the fatty acid is not completely saturated with hydrogen atoms; ex's: olive oil, avocado oil, almond oil
saturated fatty acids
contains only single covalent bonds between the carbon atoms of the hydrocarbon chain. Because they lack double bonds, each carbon atom of the hydrocarbon chain is saturated with hydrogen atoms; tend to be solid at room temperature; ex's: red meat, whole milk, butter
tissue
group of similar cells that work together to perform a particular function -all of our organs are made up of a combination of the 4 types of these.
solvent
in a solution, this substance dissolves another substance (known as the solute); Ex: your sweat is a dilute solution of water (this substance) plus small amounts of salts (the solutes). -usually there is more of this than solute in a solution -water is the most versatile of these
electrolytes
ionic bonds that dissolve in a solution. Ex's: K+, Na+, Cl-
endocytosis
materials move into a cell in a vesicle formed from the plasma membrane -require energy supplied by ATP; transport in vesicles is an active process -3 types
amphipathic
molecules that have both polar and non-polar parts
"down the concentration gradient"
moving from an area of high concentration to an area of low concentration; in many cases, a substance will move across a plasma membrane in this way to reach equilibrium
anions
negatively charged ions. Ex's: Cl-, Po4- (chloride, phosphorus)
transport maximum
number of carriers available in a plasma membrane places an upper limit on the rate at which facilitated diffusion can occur; a limited number of molecules can be moved by the carrier
catabolism
one phase of metabolism; the breakdown of complex chemical substances into simpler components. Ex: digestive processes split proteins in food into amino acids
anabolism
one phase of metabolism; the building up of complex chemical substances from smaller, simpler components. Ex: amino acids build new proteins that make up body structures such as muscles and bones.
cations
positively charged ions. Ex's: Ca++, Na+, K+ (calcium, sodium, potassium)
receptor (integral)
recognizes specific ligand and alters cell's function in some way. Ex: antidiuretic hormone binds to ______ in the kidneys and alters the permeability of water through specific cells
reproduction
refers to either: the fertilization of an egg by a sperm at the beginning of a new life or: the formation of new cells in order to repair, replace, or grow new tissue.
electrochemical gradient
refers to how a positively charged substance will tend to move toward a negatively charged area, and a negatively charged substance will tend to move toward a positively charged area. The combined influence of the concentration gradient and the electrical gradient on movement of a particular ion is referred to as this.
responsiveness
refers to the ability of the human body to detect changes in the environment and make an appropriate response. Ex's: turning your head towards the sound of squealing breaks is a response to change in the external environment; an increase in body temp during fever is a response to change in one's internal environment
exergonic reactions
release energy (usually as heat) by breaking a bond; release more energy than they absorb. Ex: glucose
endergonic reactions
require energy for the reaction to occur; absorb more energy than they release
negative feedback systems
reverses a change in a controlled condition; the response reverses the stimulus. Ex's: regulation of blood pressure; regulation of body temp: shivering in response to being in a cold room; the shivering (response) reverses the cold room (stimulus).
inorganic compounds
structurally simple molecules that usually lack carbon; include water, salts, acids, and bases.
tonicity
the concentration of salt solutions in the blood
physiology
the science of body functions; the study of homeostasis of the organ systems and their integrative functions
anatomy
the study of body structure
metabolism
the sum of all chemical processes that occur in the body; 2 phases: catabolism and anabolism
chemical reaction
when new bonds form or old bonds break between atoms; the foundation of all life processes. Ex: hydrogen and oxygen molecules react to form water molecules. -reactants = the starting substances -products = the ending substances
cellular diversity
•The average adult has nearly 100 trillion cells. •There are about 200 different types of cells. •Cells come in a variety of shapes and sizes. •This diversity permits organization of cells into more complex tissues and organs.
cell identity protein (glycoprotein)
Distinguishes your cells from anyone else's (unless you are an identical twin). An important class of such markers are the major histocompatibility (MHC) proteins.
secondary active transport
Indirectly uses ATP by piggy-backing off the electrical current generated by a channel that uses ATP; energy stored in an ionic concentration gradient is the source of this transport
the integumentary system
components: skin and associated structures such as hair, fingernails and toenails, oil glands, and sweat glands. Functions include: -protecting the body -regulating body temperature -eliminating some wastes -detecting sensations such as touch, pain, warmth, and cold -stores fat and provides insulation -synthesizing vitamin d
catabolic reaction
decomposition reactions; split up large molecules into smaller atoms, ions, or molecules; breaking apart larger reactant molecules into smaller products (exergonic); AB --> A + B; ex: CH4 ---> C + 2H2 ( a methane molecule can decompose into one carbon atom and two hydrogen molecules) -these reactions are usually exergonic because they release more energy than they absorb. -ex's: digestion and cellular respiration: breaking apart sugars and fats for energy. Ex: sucrose ---> glucose + fructose: C12H22O11--> C6H12O6+ C6H12O6.
molecules
groups of 2 or more atoms. Ex: O2: two oxygen atoms sharing electrons
control center
sets the narrow range or set point within which a controlled condition should be maintained; evaluates the input it receives from receptors, and generates output (nerve impulses; hormones; chemical signals) commands when they're needed -this is an efferent pathway since the info flows away from the control center
active transport
solutes moving against their concentration gradient; energy-requiring process that moves material across the cell membrane against the concentration gradient
positive feedback systems
strengthens or reinforces a change in one of the body's controlled conditions; the response enhances the stimulus. Ex: normal childbirth *only way to get this system to stop is by removing the stimulus
anatomy & physiology
structure and function of the body are closely related
activation energy
the collision energy needed to break the chemical bonds of the reactants; this initial energy is needed to start a reaction
osmosis
the net movement of water through a selectively permeable membrane from an area of high water concentration to one of lower water concentration
exocytosis
materials move out of a cell by the fusion with the plasma membrane of vesicles formed inside the cell. -require energy supplied by ATP; transport in vesicles is an active process
ions
atoms with a positive charge or a negative charge: cations and anions
rate of diffusion depends on
-the concentration gradient: the greater the difference in concentration between the two sides of the membrane, the higher the rate of diffusion. -temperature: the higher the temperature, the faster the rate of diffusion. Ex: all of the body's diffusion processes occur more rapidly in a person with a fever. -mass of substances: The larger the mass of the diffusing particle, the slower its diffusion rate. Smaller molecules diffuse more rapidly than larger ones. -surface area: the larger the membrane surface area available for diffusion, the faster the diffusion rate. For example, the air sacs of the lungs have a large surface area available for diffusion of oxygen from the air into the blood. -diffusion distance: the greater the distance over which diffusion must occur, the longer it takes. Diffusion across a plasma membrane takes only a fraction of a second because the membrane is so thin. In pneumonia, fluid collects in the lungs; the additional fluid increases the diffusion distance because oxygen must move through both the built-up fluid and the membrane to reach the bloodstream.
secondary active transport mechanisms
Antiporters- Carry two substances across the plasma membrane in opposite directions. Symporters- Carry two substances across the plasma membrane in the same direction.
linker (integral and peripheral)
Anchors filaments inside and outside the plasma membrane, providing structural stability and shape for the cell. May participate in moving the cell or linking two cells together
mitochondria
Powerhouse of the cell, organelle that is the site of ATP (energy) production -More prevalent in physiologically active cells: muscles, liver and kidneys
hydrostatic pressure
Pressure exerted by a volume of fluid against a wall, membrane, or some other structure that encloses the fluid. -Ex: equilibrium is reached when just as many water molecules move from right to left due to this pressure as move from left to right due to osmosis
plasma membrane
Structure: -forms the cell's flexible outer surface, separating the cells internal environment from the external environment. -it's selectively permeable, meaning it controls what goes in and out of the cell Functions: -covers and protects the cell -controls what goes in and what goes out (selectively permeable) -links to other cells -flies certain "flags" to tell other cells "who" it is -enzymatic reactions
osmotic pressure
The amount of pressure needed to restore the starting condition. Notice that this pressure does not produce the movement of water during osmosis. Rather it is the pressure that would prevent such water movement.
movement
a change in position or location: includes motion of the whole body, individual organs, single cells, and even tiny structures inside cells. Ex's: walking; running; white blood cells moving through the bloodstream to clean and repair an infected area, etc.
feedback system
a cycle of events in which the status of a body condition is monitored, evaluated, changed, re-monitored, reevaluated, etc. -each monitored variable, such as body temp., blood pressure, and blood glucose is termed a controlled condition. Any disruption that changes a controlled condition = a stimulus. * 3 basic components: receptor, control center, and effector. * two types: positive and negative
electrical gradient
a difference in electrical charges between two regions; because it occurs across the plasma membrane, this charge difference is called membrane potential. -Typically, the inner surface of the plasma membrane is more negatively charged and the outer surface is more positively charged.
concentration gradient
a difference in the concentration of a chemical between two regions; Ex: many ions and molecules are more concentrated in either the cytosol or the extracellular fluid; oxygen molecules and sodium ions (Na+) are more concentrated in the extracellular fluid than in the cytosol; the opposite is true of carbon dioxide molecules and potassium ions (K+).
receptor-mediated endocytosis
a highly selective type of endocytosis by which cells take up specific ligands. (Recall that ligands are molecules that bind to specific receptors.) A vesicle forms after a receptor protein in the plasma membrane recognizes and binds to a particular particle in the extracellular fluid. Ex: cells take up cholesterol-containing low-density lipoproteins (LDLs), transferrin (an iron-transporting protein in the blood), some vitamins, antibodies, and certain hormones by receptor-mediated endocytosis.
simple diffusion
a passive process in which substances move freely through the lipid bilayer of the plasma membranes of cells without the help of membrane transport proteins. -Non-polar, hydrophobic molecules move across the lipid bilayer through the process of simple diffusion. Such molecules include oxygen, carbon dioxide, and nitrogen gases; fatty acids; steroids; and fat-soluble vitamins (A, D, E, and K). -Small, uncharged polar molecules such as water, urea, and small alcohols also pass through the lipid bilayer by simple diffusion. -________ ____________ through the lipid bilayer is important in the movement of oxygen and carbon dioxide between blood and body cells, and between blood and air within the lungs during breathing. It also is the route for absorption of some nutrients and excretion of some wastes by body cells.
channel-mediated facilitated diffusion
a solute moves down its concentration gradient across the lipid bilayer through a membrane channel. Ex: the passage of potassium ions through a gated K+ Channel (ions move along their concentration gradient) -Most membrane channels are ion channels, integral transmembrane proteins that allow passage of small, inorganic ions that are too hydrophilic to penetrate the non-polar interior of the lipid bilayer. -Each ion can diffuse across the membrane only at certain sites. -In typical plasma membranes, the most numerous ion channels are selective for K+ (potassium ions) or Cl− (chloride ions); fewer channels are available for Na+ (sodium ions) or Ca2+ (calcium ions). -Diffusion of ions through channels is generally slower than free diffusion through the lipid bilayer because channels occupy a smaller fraction of the membrane's total surface area than lipids; still a very fast process though.
a generalized cell
all eukaryotic cells are composed of 3 main parts: 1. Plasma membrane: forms the cell's flexible outer surface, separating the cell's internal environment (everything inside the cell) from the external environment (everything outside the cell). 2. Cytoplasm: a gelatin-like substance, plus structural fibers and organelles; consists of all the cellular contents between the plasma membrane and the nucleus; cytosol = the fluid portion and organelles: little organs that carry out specific funtions 3. Nucleus: contains the genetic library of the cell; houses most of the cell's DNA
organic compounds
always contain carbon (and often hydrogen) and are usually large, complex molecules -contain a carbon skeleton: a chain of carbon atoms -carbon atoms most often bind to H, O, N, S, P -they're often very large molecules and some do not dissolve in water making them useful building blocks for the human body -carbs, fats, and proteins are all this kind of compound -make up the remaining 38-43% of the body
proteins
an organic compound; Large molecules made up of amino acid chains; contain carbon, hydrogen, oxygen, and nitrogen; they make up most cellular molecules; enzymes are examples of these. Functions: -they're used in most chemical reactions (enzymes); ex's: salivary amylase; sucrase; ATPase. -some work as "motors" to drive muscle contractions -act as signaling molecules within and between cells -provide cellular structural support; ex: collagen in bone and connective tissues; keratin in skin, nails, and hair -transport: they carry vital substances throughout the body -antibodies are an example; they defends against microbes -function as hormones that regulate various physiological processes; control growth and development
carbohydrates
an organic compound; energy storage used to generate ATP synthesis; we need these for energy -they include sugars, glycogen, starches, and cellulose. -represent only 2-3% of total body mass -contain carbon, hydrogen, and oxygen
lipids
an organic compound; they contain a large amount of calories for energy storage and production; they combine with proteins for transport within the blood; they act as insulation in the body -they're insoluble in water (hydrophobic) -fatty acids are the simplest: saturated or unsaturated -triglycerides: main form of ____ storage; they have unlimited storage in adipose tissue. Ex's include animal fat like red meat and butter.
nucleic acid
chain of nucleotides; huge organic molecules that contain carbon, hydrogen, oxygen, nitrogen, and phosphorus; DNA (forms the inherited genetic material inside each human cell) and RNA (relays instructions from the genes to guide each cell's synthesis of proteins from amino acids.) -The nucleotide adenine is the foundation of the energy-carrying molecule adenosine triphosphate (ATP); ATP is used as brief storage of energy
nervous system
components: brain, spinal cord, nerves, and special sense organs such as eyes and ears. Functions include: -regulating body activities by generating action potentials (nerve impulses) -detecting changes in the internal and external environment -interpreting information -causing muscle contractions and gland secretions
muscular system
components: skeletal muscle tissue: muscle usually attached to bones + other muscle tissues (smooth and cardiac). Functions include: -producing body movements -stabilizing body position/maintaining posture -generating heat
epithelial tissue
consists of cells arranged in continuous sheets, in either single or multiple layers.; covers body surfaces and lines hollow organs, body cavities, and ducts; it also forms glands. This tissue allows the body to interact with both its internal and external environments; it protects, secretes (mucus, hormones, and enzymes), absorbs (nutrients in the gastrointestinal tract), and excretes (various substances in the urinary tract). -this tissue is avascular; there are no blood vessels in this layer of tissue; relies on the blood vessels of the adjacent connective tissue to bring nutrients and remove wastes. -there is a nerve supply in this tissue -high regeneration rate for renewing and repairing tissue because this tissue is exposed to the external environment; it is repeatedly subjected to physical stress and injury. A high rate of cell division allows epithelial tissue to constantly renew and repair itself by sloughing off dead or injured cells and replacing them with new ones. -they are named according to arrangement and shape
hydrophilic molecules
dissolve easily in water; ex: sugar, salt
hydrophobic molecules
do not dissolve in water; ex: oils, fat/lipids
primary active transport
energy derived from hydrolysis of ATP changes the shape of a carrier protein, which "pumps" a substance across a plasma membrane against its concentration gradient. Indeed, carrier proteins that mediate primary active transport are often called pumps. -directly used ATP to power movement across the membrane
anabolic reaction
synthesis reaction; when two or more atoms, ions, or molecules combine to form new and larger molecules (endergonic); A (atom, molecule or ion) + B (atom, molecule or ion) ---> AB (new, larger molecule). Ex: 2H2 + O2 combine to form 2H2O (2 hydrogen molecules and one oxygen molecule combine to form two molecules of water) -all of the synthesis reactions that occur in the body are referred to as these; these reactions are usually endergonic because they absorb more energy than they release. -require the input of energy -ex: glucose + glucose ----> glycogen -ex: photosynthesis: CO2+H2O---> C6H12O6 + O2
phospholipids
the major lipid component of cell membranes; they have a polar head that's soluble in water and 2 non-polar tails that are soluble in fat; Molecules that have both polar and non-polar parts are said to be amphipathic. Amphipathic _______ line up tail‐to‐tail in a double row to make up much of the membrane that surrounds each cell -because they make up a major component of the cell membrane, they play a key role in determining what enters and exits a cell.
water
the most abundant and important organic compound in the human body; makes up 55-60% of the adult body mass -polarity: most important property of this; makes it an excellent solvent for other ionic or polar substances; gives these molecules cohesion (the tendency to stick together); and allows it to resist temperature change; acts as a lubricant
differentiation
the process by which an unspecialized cell becomes a specialized cell. *Stem cells = the precursor cells that can divide and give rise to cells that undergo this process. Ex: red blood cells and several types of white blood cells all arise from the same unspecialized precursor cells in red bone marrow.
passive processes
transport across the plasma membrane; a substance moves down its concentration or electrical gradient to cross the membrane using only its own kinetic energy (energy of motion). Kinetic energy is intrinsic to the particles that are moving. There is no input of energy from the cell. Ex: simple diffusion. -substances move across the cell membranes without the use of any energy -still requires transporters-they are said to move "with" or "down" their concentration gradient
active processes
transport across the plasma membrane; cellular energy is used to drive the substance "uphill" against its concentration or electrical gradient. The cellular energy used is usually in the form of adenosine triphosphate (ATP). Ex: active transport. -involve the use of energy,primarily from the breakdown of ATP, to move a substance against its [gradient].
carrier (integral)
transports a specific substance across membrane by undergoing a change in shape. Ex: amino acids, needed to synthesize new proteins, enter body cells via these transporters.
disaccharides
type of carb; consist of 2 monosaccharides; simple sugars formed from the combination of two monosaccharides by dehydration synthesis; ex's include: sucrose (table sugar) = glucose + fructose. Lactose (milk sugar) = glucose + galactose. Maltose = glucose + glucose.
polysaccharides
type of carb; consist of a long chain of monosaccharides joined by dehydration synthesis; ex's include starch, glycogen, and cellulose (fiber)
monosaccharides
type of carb; most simple type of carb; absorbable; simple sugars that contain 3-7 carbon atoms; ex's include glucose (main blood sugar), fructose (found in fruit), galactose (in milk sugar), deoxyribose (in DNA), and ribose (in RNA)
water follows solute
water passes through the plasma membrane in 2 ways: 1. through the lipid bilayer by simple diffusion 2. through aquaporins: (AQPs): integral membrane proteins that function as water channels; they play a critical role in controlling the water content of cells. -Different types of AQPs have been found in different cells and tissues throughout the body. They're responsible for the production of cerebrospinal fluid, aqueous humor, tears, sweat, saliva, and the concentration of urine.
