Unit 2-Cell Structure Review Flashcards
Prokaryotes are what domains of life
Bacteria and Archaea
Eukaryotes are what domain of life
Eukarya
Cells that are more complex and larger and usually static
Eukaryotic
Cells that are smaller and less complex and usually more mobile
Prokaryotic
what is a Cell
smallest living unit of an organism
All cells have…
membrane, cytoplasm, DNA, and ribosomes
3 Rules of cell theory
- all organisms are composed of 1 or more cells
- cells are the basic unit of structure and function in organisms
- all cells come from preexisting cells
Cellular organization, smallest to largest
cell, tissue, organ, organ system, organism
Are Prokaryotes unicellular or multicellular?
unicellular
Are Eukaryotes unicellular or multicellular?
they can be either, but usually multicellular
Do Eukaryotes have a nucleus?
Yes
Do Prokaryotes have a nucleus?
No
Do Prokaryotes have stranded or circular DNA?
Circular
Do Eukaryotes have stranded or circular DNA?
Stranded
Why are cells small?
- makes it easier to maintain homeostasis
- takes less energy to transport substances
Only plant cells have…
Cell wall, large permanent vacuole, chloroplast
What are vacuoles?
membrane enclosed structures that store water, salt, protein or carbs.
Turgor Pressure
The force exerted by stored water pushing cytoplasm against the cell wall, happens in plants
Vesicles
stores and moves materials between organelles and cell surface
Lysomes
breaks down old organelles with hydrolytic acid, breaks down lipids carbs and protein to be used by the cell
Cytoskeleton
microtubules and microfilaments (protein) that maintain the shape and assist with the movement of a cell
What organelles synthesize protein
ribosomes and ER
Ribosomes
produce protein by following DNA code
Golgi Apparatus
modifies, sorts, packages material from ER to be stored in cell or removed
Endoplasmic Reticulum
once proteins leave ribosomes, they enter the ER and are modified
Rough ER
portion associated with protein synthesis, covered in ribosomes
Smooth ER
Assembly line with no ribosomes
Explain the Steps of protein construction
- proteins are assembled in ribosomes with instructions from nucleus
- proteins and ribosomes leave the nucleus and are inserted into the ER
- after being modified the proteins leave the ER in vesicles and go to GA
- after being sorted they leave the GA in a vesicle and go where they need to
Chloroplast
location of photosynthesis
Mitochondria
converts chemical energy in food into usable compounds, contains its own DNA, like a cell within a cell
Cell Membrane
regulates what goes in and out of a cell (selectively permeable), regulates homeostasis
Selectively permeable
Only allows some substances to pass through
Cell Wall
Not a part of animal cells,
porous- allows H2O, CO2, O, and some other materials to pass through.
Cillia
hairs on the outside of cells that move like tiny arms in order to move a cell
Flagella
tail or whip like structure that moves a cell
Cillia and Flagella are found in what type of cells?
Prokaryotic
3 structures Eukaryotes have?
- nucleus
- membrane bound organelles
3.DNA held in nucleus
What four kingdoms include Eukaryotes
Plant, Animal, Fungi, Protist
Centriole
- helps with mitosis by pulling the chromosomes apart using spindles
What is the advantage of the cell membrane being selectively permeable?
Small, essential molecules can freely pass through, but other things can’t simply freely enter or exit the cell
What is the advantage of certain organelles being highly folded within?
Increase surface area for reactions to occur
Explain the difference between osmosis and diffusion.
Osmosis is the diffusion of water molecules across a selectively permeable membrane
what happens to a cell placed in a hypertonic solution.
A cell in a hypertonic solution will shrink because it has a higher water concentration than the outside solution. Water will move out of the cell
what happens to a cell placed in a hypotonic solution.
A cell in a hypotonic solution will swell because it has a lower water concentration than the outside solution. Water will move into the cell
what happens to a cell placed in an isotonic solution.
The cell will maintain its shape
A blood cell has the same concentration of solutes as seawater. What would happen to the blood cell if it were placed in a container of distilled (pure, which means 100%) water?
Water would be taken into the cell because the outside substance has a higher water concentration. This would cause the cell to swell.
In the bloodstream, the concentration of oxygen is 80%. The concentration of carbon dioxide is 20%. In the cell, the concentration of oxygen is 15%. The concentration of carbon dioxide is 85%.
Oxygen from the bloodstream will move into the cell and carbon dioxide from the cell will move into the blood street.
what part of the semipermeable membrane is hydrophilic
the head
What dose hydrophilic mean
they like water
what part of the phospholipid is hyrophobic
The nonpolar tails
What dose hydrophobic mean
doesn’t like water.
Role of cholesterol in phospholipid bilayer
Controls how close the phospholipids get to one another. Stabilizes
Peripheral Proteins
Sit on top of the bilayer
Integral Proteins
go through the bilayer
Ion channel
Proteins that allow ions to pass through cell membrane (passive)
Protein pump
Uses energy to force substances through the cell membrane (Active)
Aquaporin
Proteins that allow water to pass through the cell membrane (Passive)
2 characteristics that determine how a substance travels across the membrane
Size, Polarity
what molecules can NOT easily pass through the cell membrane
Ions, charged substances (polar) don’t pass through the lipid bilayer
why do cells have different membrane carbohydrates
So they can organize themselves and identify themselves as part of that organism.
what substance completes facilitated diffusion
channel proteins
Do negative ions or positive ions complete facilitated diffusion?
negative ions
Hypertonic solution
Has a higher solute concentration
Hypotonic solution
Has a lower solute concentration
Isotonic Solution
Equal in solution
Endocytosis
the taking in of matter by a living cell by invagination of its membrane to form a vacuole.
Exocytosis
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.
