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102 terms

Chapter 7 Cellular Structure and Function

the orderly structure shown by living things
is the basic structural and functional unit of all living organisms
cell theory
one of the fundamental ideas of modern biology and has 3 principles 1) cells are basic unit of structure 2) have one or more cells 3) arise from previously existing cells
eukaryotic cells
contains a nucleus and other organelles that are the bound by membranes, also referred to as membrane bound organelles
-multicellular organisms
-have a nucleus
-have a membrane bound organelles
-unicellular organisms
-contains organelles
is a distinct central organelle that contains the cell's general material in the form of DNA
plasma membrane
us a special boundary helps control what enters and leaves the cell
prokaryotic cell
cells without a nucleus or other membrane bound organelles
-do not have membrane young organelles
-have lose strands of DNA
-unicellular organisms
-contains organelles
three main ideas of the cell theory
1)All living organisms are composed of one or more cells
2) Cells are the basic units of structure and organization of all living organisms
3)Cells arise only from previously existing cells, with cells passing copies of the genetic material onto their daughter cells
an atom or group of atoms with a positive or negative electric charge
fluid mosaic model
a plasma membrane with components constantly in motion, sliding past one another within the lipid bilayer
phospholipid bilayer
two layers of phospholipids are arranged tail-to-tail. In the plasma membrane, phospholipids arrange themselves in a way that allows plasma membrane to exist in the watery environment
selective permeability
by which a membrane allows some substances to pass through while keeping others out
transport protein
more needed substances or waste materials through the plasma membrane and therefore contributes to the selective permeability of the plasma membrane
Five ways that the membrane can deal with materials
1) keeping molecules out
2) allowing molecules in at any time
3)allowing molecules only at certain times
4)allowing molecules in only in limited amounts
5)expelling wastes from inside the shell
a protein that speeds up the rate of a chemical reaction
cell structures
1)cell wall
related to genetic material
food, storage, and waste
1) golgi apparatus
3)endoplasmic reticulum
contains chlorophyll (photosynthesis)
membrane-bound organelle that converts fuel into energy that is available to the rest of the cell
temporary storage of materials
important for all cell division
short, hairlike projection that functions in cell movement wave-like motion
long, tail-like projection with whip-like motion that helps cells move
the environment inside the plasma membrane is a semi-fluid material. Is in prokaryotic and eukaryotic cells
is a supporting network of long, thin protein fibers that form a framework for the cell and provide an anchor for the organelles inside a cell
in eukaryotic cells -- central bound organelle that directs cell processes; contains the cell's DNA; stores information for cell growth, function, and reproduction
nuclear envelope
double membrane that surrounds the nucleus
helps manufacture proteins
produces ribosomes inside the nucleus of eukaryotic cells
endoplasmic reticulum
highly folded membrane system in eukaryotic cells that is the site for protein and lipid synthesis
golgi apparatus
flattened stacks of tubular membranes that modifies, sorts, and packages proteins into vesicles and transports them to other organelles or out of the cell
membrane-bound vesicle for temporary storage of materials such as food, enzymes, and wastes
vesicles that contains substances that digest excess or worn-out organelles
organelle that plays a role in cell division and is made of microtubules
converts fuel particles (sugars) into useable energy
double membrane organelle that captures light energy and converts it to chemical energy through photosynthesis
cell wall
in plants - the rigid barrier that surrounds the outside of the plasma membrane, is made of cellulose, and provides support and protection to the cell
cillia / flagella
projections that allow the cells to move or move to substances along the surfaces along the surface of the cell
plant cells only
-larger vacuoles
-cell walls
Both plant and animal cells
-endoplasmic reticulum
-golgi apparatus
-plasma membrane
animal cells only
-smaller vacuoles
energy-requiring process by which large substances from the outside environment can enter a cell
active transport
movement of substance from a region of lower concentration to a region of high concentration
net movement of particles from an area where there are many particles of the substance to an area where there are fewer
hypertonic solution
a solution that has a higher concentration of solutes outside the cell than inside the cell, causing water to leave the cell by osmosis (cell will shrink).
isotonic solution
a solution in which the inside of the cell and the solution it is in have the same concentration of water and solutes as the outside, resulting in the cell retaining its normal shape because there is no net movement of water
energy-requring process by which a cell expels wastes and secrets substances at the plasma membrane
diffusion of water across a selectively permeable membrane
facillitated diffusion
form of transport that uses transport proteins to move other ions and small molecules across the plasma membrane
dynamic equilibrium
condition in which there is continuous movement but overall change in concentration
hypotonic solution
a solution that has a lower concentration of solutes outside than inside the cell, causing water to flow into the cell by osmosis (cell will swell)
water and the plasma membrane
-water flows freely into and out of the cell
-osmosis is the diffusion of water across a selectively permeable membrane
-flow through helps create and maintain homeostasis
-homeostasis is organism maintains conditions suitable for life
name the invention that helped scientists discover the cell
the microscope
tell why hooke called the structures he saw in the cork cellulae ("small rooms")
the boxlike cells of cork reminded him of the cells in which monks live at a monasty
name the microscope that uses a series of magnifying lenses
compound light microscope
The _______ includes the following.
cell theory
All living organisms are composed of one or more _______.
Cells are basic unit of structure and organization of all living___________.
Cells arise only from previously existing cells, with cells passing copies of their ________ onto their _________.
genetic material to their daughter cells
E or P organisms that break down molecules to generate energy
p and e
E or P organisms that have cells lacking internal membrane - bound organelles
E or P organisms whose cells do not have a nuclei
E or P organisms that have either unicellular or multicellular
E or P organisms that are generally unicellular
E or P organisms that have cells containing organelles
E or P organisms that have plasma membranes
p and e
The process of maintaing balance inside a cell
A boundary between a cells and its environment
plasma membrane
the feature of the plasma membrane that keeps some substances out
selectively permeable
separates prokaryotic and eukaryotic cells form the watery environment in which they exist
plasma membrane
The quality of a plasma membrane that allows oxygen and glucose to move in
selectively permeable
Maintained by the plasma membrane
makes up most of the molecules in the plasma membrane
a molecule that has a glycerol backbone, two fatty acid chains, and a phosphate - containing compound
move substances through the plasma membrane
transport protein
two layers of phospholipids arranged tail-to-tail
phospholipid bilayer
the phospholipid "sea" in which embedded substances float
fluid mosaic model
light vs. electron microscope
light- color and living things
electron- no color dead things
specialized internal cell structure that carries out specific cell functions such as protein synthesis and energy transformation
The _______ is a structure that surrounds a cell and helps control what enters and exits the cell.
plasma membrane
A _______ has membrane - bound organelles
_____are basic units of all organisms
If a microscope has a series of three lenses that magnify individually 5x, 5x, and 7x what is the total magnification of the microscope?
Why might a microscopist, who specializes in the use of microscopes to examine specimens, use a light microscope instead of an electron microscope?
The light microscope can see in color and things that are alive.
A _______ is the basic structure that makes up the plasma membrane.
______ proteins move needed substances or waste materials through the plasma membrane.
________ is the property that allows only some substances in and out of the cell.
selectively permeable
Which situation would increase the fluidity of a phospholipid bilayer?
increasing the number of cholesterol molecules
How does the orientation of the phospholipids in the bilayer allow a cell to interact with its internal and external environments?
polar heads outside the cell
non polar head inside the cell
What might happen to a cell if it no longer could produce cholesterol?
the cells plasma membrane would be less fluid and homeostasis can't be maintained
______stores wastes
______produces ribosomes
________generates energy for a cell
________sorts proteins into vesicles
Golgi apparatus
Which structure synthesizes proteins that will be used by the cell?
Which id the site of protein synthesis?
endoplasmic reticulum
In which structure would you expect to find a cell wall?
cell from an oak tree
Compare the chloroplast to the mitochondrion.
Chloroplast- double membrane organelle with thylakoids containing chlorophyll (photosynthesis) light energy to chemical energy
Mitochondrion- a membrane bound organelle that makes energy chemical to APT
What factors affect the rate of diffusion?
Which type of transport requires energy input from the cell?
active transport