Cell Structure And Function Flashcards
What Features are shared by all cells?
Organisms are made up of 1 or more cells.
The cell is the basic unit of structure and function of living things.
Cells arise from previously existing cells
Exceptions to cell theory:
The 1st cell could not have arisen from a previously existing cell.
Mitochondrion and chloroplasts contain their own DNA; can self-replicate inside of cells.
Viruses contains DNA and proteins but smaller than cells, lack organelles.
Are non living
Separates cell contents from the external environment.
Regulates what comes in and out of the cell.
Cell membrane
Is made up of a double layer of phospholipids— the Lipid By-Layer
Is embedded with other molecules such as proteins- “fluid mosaic”
Cell membrane
Consists of DNA wrapped in a protein coating.
Non-living because It can on,y reproduce inside living cells (host cells)
VIRUSES
Types of cells
Prokaryote.
Eukaryote.
No nucleus ( non-membrane bound organelles) Ex. Bacteria Cells
Prokaryote
Has a nucleus and membrane bound organelles.
Ex. Plant and animal cells
Eukaryote
Hydrophilic head groups line the exterior of the membrane.
Hydrophobic tail groups line the interior
Phospholipid
cell membrane is:
Selective Permeable
Small molecules pass through easily.
large molecules less easily.
Window screen analogy
Selectively Permeable
movement of material from an ara of high concentration to an area of low concentration.
1 way molecules pass through cell membrane
Diffusion
for diffusion to occur, there must be a :
Concentration Gradient
A difference in concentrations from 1 place to another.
Concentration Gradient
the result of diffusion when everything is evenly distributed.
Dynamic Equilibrium
osmosis
the diffusion of water
can affect cells in different ways.
hypotonic, Isotonic, and hypertonic solutions describe the types of environments a cell may be exposed to
Osmosis
higher sal concentration inside of the cell than outside. (EX. more water outside of the cell).
So, H2) diffuses into the cell, causing it to swell or burst.
Ex. Red blood cell in Distilled water
Hypertonic Solutions
Has same concentration outside the cell as inside the cell.
So, H20 diffuses in and out of the cell at the same rate.
Ex. Fluid surrounding body cells is isotonic
Isotonic Solutions
Higher sal concentration outside of cell than inside.(Ex. more water inside the cell).
So, H20 diffuses out of the cell, causing it to shrivel.
Ex. Elodea in saltwater
Hypertonic Solutions
Where cellular Respiration occurs (Energy release).
May have originated from prokaryotic cell
Mitochondrion
Fluid-filled canals.
Tubes for transport of materials.
Site of lipid synthesis.
Smooth Endoplasmic Reticulum
A portion of ER that’s Lined with ribosomes
Rough ER
site of protein synthesis.
Found on rough ER and in Cytoplasm
Ribosomes
