Name: ________________________________Cytology Guided Notes

Cell Theory1. All living things are __________________ of cells2. Cells are the basic _______________________ of __________________3. All cells come from ____________________________ cells

Important People1) Anton von Leeuwenhoek – made the ___________________________________________________________2) Robert Hooke – discovered ____________________ by looking at cork (dead _________________ cells)3) Matthias Schleiden – German botanist; said all _______________________ are made up of cells4) Theodor Schwann – German zoologist; said all _______________________ are made up of cells5) Rudolf Virchow – German physician; said all cells come from _____________________ cells

Reasons why Cells are Small Surface Area (SA) to Volume ratio • Cell Size is limited, because…

1) Volume ______________________________ much faster than the ________________________ area2) ______________________________ doesn’t happen fast enough!

• Creates an imbalance in nutrients, oxygen, & waste à the cell can _____________________ or ___________________________ itself

• The _______________________________ the SA:Volume ratio, the more efficient processes (ex: oxygen entering/exiting) will be!

CELLS!• Smallest unit of life in all ______________________ things• Two basic types:

Prokaryotic – • ______________________• ______________________• No ______________________ - bound ______________________• No ______________________• MAY have a cell wall • Ex: ______________________

Eukaryotic – • More complex• ______________________- bound organelles• Ex: ______________________, Animals, and ______________________

Prokaryotes:• Prokaryotes: (pro- means before, and -karyote means nucleus)

• _______________ type of cells to evolve • Very small (size of mitochondria)• ______________________• Two Types:

• 1) ______________________

• 2) ______________________1

• Cell Division/Reproduction: Asexual via Binary Fission

Three Shapes:1) ______________________ (rod shaped)

2) ______________________ (spherical)

3) ______________________ (spiral)

Prokaryotic Structure Components:• ___________________________________ (also

called a plasma membrane)• cell ___________________• ribosomes• flagella or cilia

• ______________________region (NO NUCLEUS)

• ______________________• capsule• pili• NO membrane-bound organelles

Eukaryotic Cells:• Divided into compartments• ______________________or ______________________• ______________________→ structures that have a specific ______________________in the cell (including the nucleus)

• Cytoplasm → region between nucleus and plasma membrane that surrounds organelles• Filled with ___________________ (watery-jelly part) and organelles• Contains ______________________, which help with cell division à reproduction

Types of Eukaryotes

• ______________________ (Protozoa)• Protists

• Paramecium, amoebae• Fungi

• Yeast

• ______________________ (Metazoa)• Fungi• Plants• Animals

• Reproduction for ALL eukaryotes may be ____________________________ or ______________________

Features in Common between Eukaryotes & Prokaryotes: • Both eukaryote and prokaryote cells have these features in common:

1) Surrounded by a ___________________________/cell membrane• This determines what enters and leaves the _________________________• It is thin and flexible and does not provide much structural support• Ex: ____________________________

2) Have ______________________________ • __________________________ proteins by linking amino acids (protein synthesis)

3) Have DNA or RNA as genetic material

The Cell Membrane

- Thin, flexible, surround ____________ cells

- ________________________________ the traffic of molecules _______________ and _______________ of the cell (school

doors)

- Takes in substances & disposes the cell’s waste

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- Allows substances through by either _____________________________transport ( _________ energy) or

_____________________________transport (________________________ required!)

Structure of Plasma Membrane

- Made of _____________________________

- Phosphate ____________________ and _____________________________ chains are the tail(s)

- Arranged in a _____________________________

- Heads – _____________________________

- Tails – hydrophobic

- Roots:

- _____________________________ - polar phosphate group

- ________________________ - non-polar fat

- ____________ - two

- ________________________ - sheet or quantity covering a surface

- The phospholipid bilayer is a ________________________________________ membrane

• MEANINING it only allows ______________________________ substances to diffuse across

Selective Permeability:

– Allows __________________ materials, but not all, to cross through

– Small non-polar molecules can pass ___________________ through membrane

– Small polar molecules must pass through _______________________

– _________________________ molecules must be moved with _________________________

Proteins- Two types:

1) Integral

• Permanently attached to the __________________________________________

• Transmembrane

• Found __________________________________________ the entire bilayer

• Monotopic • Attached on __________________ side of membrane and do NOT span across the

membrane2) Peripheral

• Only found “_____________________” bilayer

Cholesterol

• Cholesterol ________________________________ the membrane

• Integrates between phospholipids

• Present in ________________________________________ membranes

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• Absent in bacteria and most plants where the _________________________________ provides stability

Carbohydrates

• Carbs found on the __________________________ for identification

– Glycolipids and Glycoproteins serve as recognition sites for other cells

Fluid Mosaic Model

• Description of arrangement of ____________________________ that make up the cell membrane

– Cell Membrane is flexible, not rigid– Phospholipids can move from side to side and slide past each other

• Variety of molecules studding the membrane is similar to arrangement of tiles with different textures and patterns

Organelles:Nucleus

• Nucleus is the _____________________________ center of the cell • Ex: Main Office of a school

• Found in ____________ eukaryotes• Made of __________ additional structures:

- Nuclear envelope – surrounds nucleus; porous- _____________________________– inside the nucleus; makes ribosomes

Nucleus also contains __________________________ (stores genetic info) and some RNA• ________________________________ – coiled DNA; contains genes• _____________________________– uncoiled DNA; most common in this form, easier to copy

Endoplasmic Reticulum (ER)• Folded membranes• Moves supplies from one part of the cell to another

• This helps maintain ______________________________• Two types of ER…

• _______________________________• _______________________________

Smooth ER:• Not attached ______________________________________ (which makes it smooth)

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• Has ______________________________________ that help build molecules• Lipids (phospholipids, fatty acids, steroids, hormones, etc)

Rough ER:• Ribosomes attached to surface

• Not all ribosomes attached to rough ER (some __________________________ float) • Rough ER ___________________________ to ______________________________ membrane • Makes more membrane• Makes/modifies ___________________________________ • Proteins are transported by vesicles to the Golgi

• Vesicles “__________” off the _________________________________________

Golgi Apparatus • _________________ interconnected (flattened pancakes!)• Receives vesicles (full of ________________________) from the Rough ER• One side receives the vesicle

• Makes small modifications • After modifications, the protein is re-packaged inside a new vesicle and…

• ________________________________ to other organelles within the cell• ________________________________ in the Golgi for future use• ________________________________ outside of the cell membrane

Lysosomes• _____________________________________________/recycling center of the cell• Sac of digestive enzymes• ____________________________________ by the Rough ER and _____________________________________ by the Golgi• Breaks down “bad” organelles /parts

• “Garbage disposal” • Only in animal cells

Energy Organelles

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• Two “energy” organelles• _____________________________________• _____________________________________

• Both contain their own DNA

Chloroplast • Site of _____________________________________• Converts energy from the _______________ into chemical energy• Only in __________________________ and some Protists

Mitochondria• Site of Cellular Respiration à makes __________________

• ATP required for cell activity!!!! • ENERGY!! _________________________________ of the cell• Found in almost all eukaryotic cells• Two membranes à inner membrane is folded up to increase the _____________________

Cell Structure• Cytoskeleton

• Structural support for __________________________ cells• Helps with movement

• Made up of: • __________________________________________________ = move (in muscles) and divide• Intermediate Filaments = ___________________• _________________________________________________ = ________________________

Movement• Cilia → short and ____________________________; beat _____________________________• Flagella → ___________________; long and whip-like

Vacuoles• ________________________________ “containers”

• Store various substances• The “___________________________” of the cell

• In animals = small and numerous• In plants = one _______________________________________________________________

• Stores mostly water but also waste and nutrients• Helps with the ________________________________________ of a plant cell

Cell Structures – Plant Cells ONLY • Cell Wall

• Rigid, tough• Made of cellulose

• ____________________ Central Vacuole• Fills with water and increases turgor pressure (pressure in a cell)

• Chloroplasts

Animals vs. Plants – draw a T-chart or Venn Diagram below

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PASSIVE TRANSPORT- Three types:

1) Diffusion

2) ____________________________________

3) ____________________________________

Passive Transport

• Molecules move from a _________________ concentration à to a _________________ concentration

• Does _________________ use energy

• Remember:

– Solute à thing being _________________

– Solvent à doing the _________________ (example = _________________)

Diffusion: – Movement of molecules from a _________________ concentration to a _________________ concentration

– Does _________________ use energy

– Can occur in ______________________________ systems (example = _________________)

• Concentration :

– Number of molecules of a substance in a given volume

• Concentration gradient :

– Difference in concentration of a substance from one location to another

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Facilitated Diffusion• Molecules move _________________ (not against) a concentration gradient with the aid of special proteins

– _____________________________ up the process

– Proteins CAN change __________________

• Does use energy = type of passive transport

• Moves things from _________________ to _________________ concentrations

**Refresher – what did we see when we completed our Diffusion Baggie Test?**

Osmosis: – diffusion of ________________________ across a

membrane

• Water moves across a semi-permeable membrane

from an area of high ________________________

concentration to an area of low __________________________ concentration

• If water can cross a membrane, but the solute cannot, then…the water moves _______________ the side with

______________________________ solute to balance the concentrations

• Osmoregulation – control of water balance

• Turgor pressure – pressure ____________________________ a cell

• Tonicity – tendency of a cell to lose or gain water based on the solution it is in

3 Types of solutions:

– __________________________

– Hypotonic

– __________________________

Isotonic Solutions

• __________________________________ has same concentration of dissolved particles as the ________________

• Water moves into and out of cell at ____________________ rates and cell size remains _____________________

• Cell does _______________ change shape

Hypotonic Solutions

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• Solution has a ____________________ concentration of dissolved particles than the ____________________

– Water flows ____________________ the cell

– The cell ____________________ /gets _______________!

– Example: _______________________________________

• In animals:

• ____________________ (when a cell BURSTS!)

Hypertonic Solutions

• Solution has a ____________________ concentration of dissolved particles than the ____________________

– Water flows ____________________ of the cell

– The cell ____________________ up and turgor pressure ____________________

– Ex. _______________________________________

**What will happen to a freshwater fish if he was thrown in the ocean?!**

Let’s Practice!

1. Solution is… _________________________

  Water is going to… _____________________

2. Solution is… _________________________

  Water is going to… _____________________

3. Solution is… _________________________

  Water is going to… _____________________

4. Solution is… _________________________

  Water is going to… ___________________

5. If a cell contains 85% water and is placed into a environment which is 50% water. Is the cell hypotonic or hypertonic? In which direction will the water move, into the cell or out of the cell?

6. A cell contains 85% water and is placed into a

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solution, which contains 90% water. Is the solution in the environment hypotonic or hypertonic? In which direction will the water move?

7. If a cell which contains 90% water is placed into an isotonic solution, what percentage of the solution is water?

8. A cell contains 95% water, the environment outside the cell contains 45% solutes. Is the cell in a hypotonic or hypertonic environment?

9. A cell containing 25% solutes is placed into a solution, which contains 35% solutes. Whichdirection will the water move, into the cell or out of the cell?

ACTIVE TRANSPORT

Refresher…

• Remember, Passive Transport does NOT require energy

• Types of passive transport:

• _________________________________

• ______________________________________________

• _________________________________

Active Transport

• Requires _________________________!

• Molecules move __________________________ their concentration gradients (from ____________ concentration to

_________________)

• Cells use ____________________to power this process

• Two types: _________________________ and _________________________

Exocytosis

• USES ENERGY!

• Moves “_________________” materials ___________________ of the cell

• Vesicle moves to the plasma membrane and fuses with it, contents are emptied from the cell

Endocytosis

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• USES Energy!

• Brings ““_________________”” materials ___________________ the cell

• Three types, one major type:

• ____________________________________– “cell eating”, engulfs food and forms a vesicle around it; fuses with

___________________ and uses the contents

Additional T-Chart Notes:

1. 1.

2. 2.

3. 3.

4. 4.

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