Science 8: Biology Notes
Introduction to Cells Name: ___________________
Cells and Cell Systems
Characteristics of Living Things: Are composed of _________ Cells reproduce by ____________ into two
o This allows organisms to ________ and ___________ themselves Require ____________ Respond to their ________________ Have a life ___________ Produce __________
In order to be considered an organism … It must show ________ the characteristics of living things.
The Cell Theory States that: The __________ is the basic building block of all organisms All living organisms are composed of ________ or more ________ All cells come from _____________ cells
Cells can be sorted by … Their ___________ –skin, muscle, nerve … As _________, ___________, or ___________
o Plant and animal cells are _________ cellso Bacteria cells are not __________ cells
We call “true” cells ___________________ cells and not “true” cells prokaryotic cells.
What Makes Cells Different? To answer this we need to introduce a new term: ___________ Cells contain many different ____________ _____________ are specialized to carry out one function. Think of them as mini
___________ .
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Science 8: Biology Notes
True Animal and Plant Cells have many organelles in commonPresent in All Cells:
1. ________ membrane2. ______________3. ______________4. _____________ ER5. _____________ ER6. ________ apparatus7. _____________8. _____________9. _____________
Present in Some Cells:1. _____________2. _____________
True Plant Cells also have unique organelles:
1. Cell ___________2. ______________3. ______________ – tiny or absent
in most animal cells
Is That All That’s Known? There are many more ______________ in cells that we won’t be discussing There will probably be many more ______________ discovered as microscopy
techniques improve
Our Microscopes: Are monocular ( _______ eyepiece) Compound ( ______ lenses) Light reflected from its __________ (passes through specimen) Magnify specimens either _______ times or _______ times.
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Science 8: Biology Notes
A Closer Look at Cell Organelles as Seen by a a Light Microscope
The Nucleus Is the _________ centre for a cell It contains a cell’s ____________ which is its DNA (genetic information) Most human cells have _______ strands ( ____ from “mom” and _____ from
“dad”)
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Science 8: Biology Notes
DNA Is a special code that contains the
________ for the construction of most chemicals. These chemical make you – you!
This code is not allowed to leave the __________; it must be copied – just like a reference book cannot leave a ___________
The Cell Membrane Is the cell’s _________________. It selectively chooses
what is allowed to enter and exit. It cannot control the flow of ________ or __________.
These molecules are too small.
The Cytoplasm Is a __________ matrix that contains cell organelles. Within the cytoplasm is a scaffolding called the
_______________. The cytoplasm allows for rapid _________ of
nutrients and wastes.The Vacuole
Is a storage room for the holding of ____________ or _________. In __________ cells the vacuole occupies most of the cell. It is used to store
_____________ and to provide ____________.
The Flagellum Is a whip-like _________ that can help cells to ___________.
Cilia Are tiny ________ that work together to move a ________ or to
move _________ surrounding a cell.
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Science 8: Biology Notes
The Cell Wall Is found in _________ cells It is __________ permeable It provides ___________ for both the plant cell and the plant ___________ plants have an additional cell wall that supplies
even more support.
The Chloroplast Is a sugar assembly __________ found in green plant
cells. Carbon dioxide plus __________, in the presence of
light, react to produce ____________ and oxygen (a ___________!)
In symbols photosynthesis looks like:6 CO2 + 6 H2O + energy 1 C6H12O6 + 6 O2
A Closer Look at Cell Organelles as Seen by a Scanning Electron and Transmission Electron Microscope
Why Electrons? There is a limit to the ____________ available from light microscopes.
o Light waves are just too __________ to see spaces between tiny organelles.
Electrons … Are ____________ and are able to pass through tiny spaces – the spaces too
_________ for light to pass through If we fire a beam of electrons at a ________ sliced sample and then record
digitally where they penetrated and struck a recording plate then ,… We have a ______________ electron microscope!
TEMs allow us to build a … ______ - dimensional picture
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Science 8: Biology Notes
And … If we fire a beam of electrons at a thinly sliced sample and then record
digitally where they ___________ ___________ and struck a recording plate then …
We have a ____________ electron microscope!
SEMs allow us to build a … ________- dimensional picture of an object’s surface.
Using Observations from both a SEM and a TEM … allow graphic artists to buid three-dimensional ___________ of cells and
organelles. Biochemistry is used to determine what each organelle does ____________ for
the cell
Cell Organelles “Seen” by Electron MicroscopesMitochondria
The chemical reactions that occur inside mitochondria are part of respiration (cellular ____________ ).
All living ___________ and __________ cells must respire.
Convert the energy stored in __________ into “chemical __________” used to drive (pay for) many cell reactions.
This cell money is called ________ . Respiration involves the conversion of glucose, with the assistance of
_________, into carbon dioxide, __________, and ATP. In symbols respiration looks like:
1 C6H12O6 + 6 O2 6 CO2 + 6 H2O + 38 ATP
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Science 8: Biology Notes
Ribosomes Appear as dots in an electron micrograph. They are found ___________ to
the nuclear membrane and to the __________ ER. They are also found floating ________ in the cytoplasm. Ribosomes use the ________ of DNA to build proteins.
Rough Endoplasmic Reticulum When proteins are assembled
for cellular __________ to be used by another cell, they are built on the rough ER.
These proteins include many hormones, as well as digestive ____________.
Smooth Endoplasmic Reticulum Build special types of fats (called ________). These include ________
hormones.
Golgi Apparatus Takes generic proteins and lipids
made by the ER and tweaks their sugar _______.
These chemicals are then wrapped in a membrane and targeted for cellular _________.
Lysosomes Are ____________ plants and __________________ sites found in all animal
cells.
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Science 8: Biology Notes
Unicellular OrganismsAll unicellular organisms must:
Take in _________ , water and other ______________ Extract ____________ from food Eliminate __________ ______________
Types of Unicellular Organisms _____________ (prokaryotes) _____________ (eukaryotes) and some __________ (eukaryotes)
Bacteria Are different from plant and animal cells because:
o They have no ____________o They do not have ______________
They DO HAVE ribosomes!!!!Characteristics of Bacteria
Are all __________________ Are all __________________ Reproduce by ___________ fission (duplicating all of their “stuff” and then
splitting in two.)Not all Bacteria are Harmful
Many are _________________ Some are _________________
Bacterial ShapeBacteria come in three basic shapes:
_____________________ _____________________ _____________________
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Science 8: Biology Notes
Pathologists use characteristics like shape and clustering to help identify bacteria.
Antibiotics – Used to Fight Bacterial InfectionsWork by preventing:
• bacterial cell ____________ formation• bacterial cell ____________ function• ___________ synthesis• ___________ information synthesis
Or they interfere with other ___________ processes
Protists Most are __________________ Are _________________
o Have a _____________o Have _______________
Are ________-like, __________-like, or ___________-like Are found in __________ or __________ environments including ______________
and _______________
Plant-like Protists Have ________________ and can photosynthesize ________ Can also __________ smaller cells!!! Have a cell ______________ Produce much of our atmosphere’s ____________ Some are bioluminescent Can cause a red tide if the water is warm and full of nutrients
Animal-like Protists Move by one of the following
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Science 8: Biology Notes
o A false _________ (pseudopod)o _______________o _______________
Or do not move (these are usually ____________ )
Cells and Cell Systems
A Closer Look at Diffusion and Osmosis
Diffusion is the spreading out of _________ from an area of high _______________ to an area of low _________________.
Diffusion happens because particles are ______________.
Diffusion of water across a membrane is called ___________.
Osmosis attempts to ________________ concentration gradients of particles that cannot ___________ through a cell membrane.
As a cell gets ___________, diffusion takes longer.
There is a limit to cell size:The ________ of diffusion limits cell size. So a large organism needs _________ cells.Cells are organized into:
Ratio of Surface Area to Volume
Volume (length x width x height)
Surface Area (length x width x 6)
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Science 8: Biology Notes
_________: a grouping of cells that have similar shape and function
Cell organization continues:Different types of ___________ can be organized to form organs. ___________ have at least one ____________. Some organ examples include the: ___________, ___________, ___________, ___________, and __________.
Organization continues:___________ that have related functions can be grouped as ___________ systems. There is often overlap between the different ______________. __________ systems are combined to form an _______________.
Organ systems include the:
_____________ ____________ _____________ _____________ _____________
_____________ ____________ _____________ _____________ _____________
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Science 8: Biology Notes
Cell Wars: Defending Attacks from “Bad Boys”
Cell WarsViruses
o Some viruses cause ____________ infections; others are _____________.o Aside from ____________, there is no effective medical treatment for viral
infections.
Living Qualities of Viruses1. Have a protein _________ (capsid)2. Some have special ______________3. Have a small amount of __________ material
Non-living Qualities of Viruses1. Non-______________2. Do not __________3. Do not make or use ____________4. Do not _____________ to their environment5. Cannot reproduce on their ________________6. Can be _________________
So???:o Since viruses need to invade cells to _________________; they are not
considered ______________ organisms.
Virus ReproductionThere are two main kinds of virus reproduction:
1. destroy the host cell ___________________2. virus goes ________________ in host cell possibly for many years
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Science 8: Biology Notes
To Reproduce1. virus _________ its genetic material into a host cell2. genetic material takes over the cell’s __________________3. the cell makes virus ___________ 4. viruses assemble and the cell _____________ releasing the new viruses 5. newly released virus particles attack other _____________
How Our Bodies Fight Microscopic Invaders
Before the invader enters, we rely on:o Our __________ to act as a barriero Secretions like ____________, _____________, ____________ and – yuck! She
means ear wax!o The ___________ in our stomach
Once the invader is inside we rely on:o _________ Blood Cells to save us.o WBCs swallow the ____________ or ____________ damaged by invaders; or:o WBCs to produce _____________ that mark the invaders or damaged cells for
destruction by other WBCs
Antibodieso Are ____________ to the invadero They work similar to a lock and _______________o Each invader (lock) requires a different _____________ (key)
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Science 8: Biology Notes
DAN, YOU WILL NEED TO DO ADDITIONAL WORK ON THE IMMUNE SYSTEM. IMMUNOLOGY AND ENDOCRINOLOGY ARE THE TWO MOST COMPEX HUMAN BODY SYSTEMS. SO … KEEP IT SIMPLE.
Cellular Respiration Is the process by which your __________ use ______________ to release e energy
(ATP) from ______________ in the ________________ . In symbols respiration looks like:
1 C6H12O6 + 6 O2 6 CO2 + 6 H2O + 38 ATP As a result of cellular respiration, ________________________________, a waste, is
produced.
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