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90 terms

unit 3: circulatory system, cell organelles, diffusion, excretory system

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cell
The simplest collection of matter that can live
cell theory
The theory that all living things are composed of cells and all cells come from other cells
microscope
an optical instrument used for viewing very small objects, such as mineral samples or animal or plant cells, typically magnified several hundred times.
magnification
An increase in the apparent size of an object
resolving power
A measure of the clarity of an image; the minimum distance that two points can be separated and still be distinguished as two separate points
light microscope
An optical instrument with lenses that refract (bend) visible light to magnify images of specimens
transmission electron microscope
A microscope that passes an electron beam through very thin sections, primarily used to study the internal ultrastructure of cells
scanning electron microscope
A microscope that passes an electron beam through very thin sections, primarily used to study the internal ultrastructure of cells
prokaryote
a microscopic single-celled organism, including the bacteria and cyanobacteria, that has neither a distinct nucleus with a membrane nor other specialized organelles
eukaryote
an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleu
ribosome
A cell organelle constructed in the nucleolus and functioning as the site of protein synthesis in the cytoplasm
plasma membrane
The membrane at the boundary of every cell that acts as a selective barrier, thereby regulating the cell's chemical composition
cell wall
A fairly rigid, chemically complex structure that exists outside the plasma membrane of most prokaryotes
flagella
A long cellular appendage specialized for locomotion, formed from a core of nine outer doublet microtubules and two inner single microtubules, ensheathed in an extension of plasma membrane
cytoplasm
a water based "jello" that organelles aer suspended in
nucleus
the genetic control center of the cell that contains DNA
chromosome
A threadlike, gene-carrying structure found in the nucleus
nuclear envelope
The membrane in eukaryotes that encloses the nucleus, separating it from the cytoplasm
endomembrane system
The collection of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles
rough ER (endoplasmic reticulum)
That portion of the endoplasmic reticulum studded with ribosomes. Makes membranes and proteins that will be secreted by the cell and embedded in the cell.
smooth ER (endoplasmic reticulum)
That portion of the endoplasmic reticulum that is free of ribosomes. Synthesizes lipids and in muscle cells it stores calcium ions.
golgi apparatus
An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulum
secretory protein
Proteins that are secreted by the cell via the endoplasmic reticulum
vesicle
A tiny membranous sac in a cell's cytoplasm carrying molecules produced by the cell
lysosome
A membrane-enclosd bag that contains enzymes and digests used up molecules and organelles for reuse
vacuole
A membrane-enclosed sac containing a variety of substances
central vacuole
a membranous sac in plant cells that supports the cell and contains water
chloroplast
An organelle found only in plants and photosynthetic protists that absorbs sunlight and uses it to drive the synthesis of organic compounds from carbon dioxide and water
mitochondria
An organelle in eukaryotic cells that serves as the site of cellular respiration
cytoskeleton
A network of microtubules, microfilaments, and intermediate filaments that branch throughout the cytoplasm and serve a variety of mechanical and transport functions
cilia
hair like structures for movement
pili
helps stick to surfaces in bacteria
centrioles
organizes DNA during cell division
peroxisome
catalase is located here which helps break down hydrogen peroxide
nucleolus
dense region of nucleus where ribosomes begin to be made
cell junction
A structure that connects cells within a tissue to one another
plasmodesmata
An open channel in the cell wall of plants through which strands of cytosol connect from adjacent cells
extracellular matrix
layers of glycoproteins, helps cells stack together, assists in cell communication
selective permeability
A property of biological membranes that allows some substances to cross more easily than others
phospholipid
A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail
receptor
A protein that binds selectively to a specific molecule and initiates a biological response
diffusion
The spontaneous tendency of a substance to move down its concentration gradient from a more concentrated to a less concentrated area
passive transport
The diffusion of a substance across a biological membrane
osmosis
The diffusion of water across a selectively permeable membrane
hypertonic
In comparing two solutions, referring to the one with a greater solute concentration
hypotonic
In comparing two solutions, the one with a lower solute concentration
osmoregulation
The control of water balance in organisms living in hypertonic, hypotonic, or terrestrial environments
facilitated diffusion
The spontaneous passage of molecules and ions, bound to specific carrier proteins, across a biological membrane down their concentration gradients
active transport
The movement of a substance across a biological membrane against its concentration or electrochemical gradient with the help of energy input and specific transport proteins
exocytosis
The cellular secretion of macromolecules by the fusion of vesicles with the plasma membrane
endocytosis
The cellular uptake of macromolecules and particulate substances by localized regions of the plasma membrane that surround the substance and pinch off to form an intracellular vesicle
capillary
A microscopic blood vessel that penetrates the tissues and consists of a single layer of endothelial cells that allows exchange between the blood and interstitial fluid
interstitial fluid
The internal environment of vertebrates, consisting of the fluid filling the spaces between cells
blood
A type of connective tissue with a fluid matrix called plasma in which blood cells are suspended
open circulatory system
An arrangement of internal transport in which blood bathes the organs directly and there is no distinction between blood and interstitial fluid
closed circulatory system
Circulatory systems in which blood is confined to vessels and is kept separate from the interstitial fluid
artery
A vessel that carries blood away from the heart to organs throughout the body
vein
A vessel that returns blood to the heart
atrium
A chamber that receives blood returning to the vertebrate heart
vetricle
A heart chamber that pumps blood out of a heart
arteriole
A vessel that conveys blood between an artery and a capillary bed
pulmonary arteries
Carry deoxygenated blood to the lungs
aorta
The largest blood vessel of the cardiovascular system
superior vena cava
A large vein that channels oxygen-poor blood from the upper body
inferior vena cava
Another large vein that drains blood from the lower body
cardiac cycle
The alternating contractions and relaxations of the heart
diastole
The stage of the heart cycle in which the heart muscle is relaxed, allowing the chambers to fill with blood
systole
The stage of the heart cycle in which the heart muscle contracts and the chambers pump blood
cardiac output
The volume of blood pumped per minute by the left ventricle of the heart
blood pressure
The hydrostatic force that blood exerts against the wall of a vessel
pulse
The rhythmic stretching of the arteries caused by the pressure of blood forced through the arteries by contractions of the ventricles during systole
plasma
The liquid matrix of blood in which the cells are suspended
platelet
A small enucleated blood cell important in blood clotting; derived from large cells in the bone marrow
red blood cell
A blood cell conaining hemoglobin, which transports oxygen
white blood cell
A blood cell that functions in defending the body against infections and cancer cells
ammonia
A small and very toxic nitrogenous waste produced by metabolism
urea
the main nitrogenous breakdown product of protein metabolism in mammals and is excreted in urine
urine
The waste material produced by the excretory system
filtrate
Fluid extracted by the excretory system from the blood or body cavity
kidney
function is to purify the blood by removing nitrogenous waste products and excreting them in the urine
ureter
A duct leading from the kidney to the urinary bladder
urinary bladder
The pouch where urine is stored prior to elimination
urethra
A tube that releases urine from the body
nephron
The tubular excretory unit of the vertebrate kidney
filtration
In the vertebrate kidney, the extraction of water and small solutes, including metabolic wastes, from the blood by the nephrons
reabsorption
The process by which water and valuable solutes are reclaimed from the filtrate and returned to the blood
secretion
the discharge of wastes from the blood into the filtrate from the nephron tubules
excretion
The disposal of nitrogen-containing waste products of metabolism
liver
prepares nitrogenous wastes for disposal, detoxifies poisonous chemicals in the blood
homeostasis
The steady-state physiological condition of the body