Chapter 7.2 Cell Structure Flashcards
What is the role of the cell nucleus?
the nucleus contains nearly all of the cell’s DNA and with it, the coded instructions for making proteins and other important molecules.
What are the functions of vacuoles?
(“vacuus” latin term for “empty”) vacuoles store materials like water, salts, proteins, and carbohydrates)
What are the functions of lysosomes?
(“Lys(o) or Lytic” Greek term for dissolution which means to break down and dissolve) lysosomes break down lipids, carbohydrates, and proteins into smaller molecules that can be used by the rest of the cell. They are also involved in breaking down organelles that have outlived their usefulness.
What is the function of a cytoskeleton?
(“cyto” Greek term for “cell”) a cytoskeleton helps the cell maintain its shape and is also involved in movement. Part of the cytoskeleton include:
- Microfilaments (made of actin)
- Microtubules (made of tubulins)
What are the functions of centrioles?
centrioles are located near the nucleus and help organize cell division. (because animal cells do not have a cell wall, just a flexible cell membrane, centrioles are not found in plant cells)
What organelles help make and transport proteins? (long version)
Instructions to make a specific protein is found in the nucleus within the code of DNA. This message gets sent out of the nucleus by making a copy of the specific strand of DNA to produce mRNA (messenger RNA). This mRNA leaves the nucleus and binds to a ribosome.
Proteins are assembled by Ribosomes (“the cell factory”) which put together specific amino acids available into longer chains.
Proteins that are meant to be released, or secreted, from the cell as well as many membrane proteins and proteins destined for lysosomes/other specialized locations within the cell will be produced by ribosomes located on the Rough Endoplasmic Reticulum (which the the presence of ribosomes on the outside of the endoplasmic reticulum why why it looks rough).
The Golgi Apparatus modifies, sorts, and packages proteins and other materials from the Endoplasmic Reticulum for storage in the cell or release outside the cell.
What organelles help make and transport proteins?
In their order of operation:
1) Ribosome
2) Endoplasmic Reticulum
3) Golgi Apparatus
What is the Endoplasmic Reticulum?
(“endo” = within”) (“reticulum” = latin for “little net)
an internal membrane system found inside of eukaryotic cells where lipid components of the cell membrane are assembled, along with proteins and other materials that will be exported out of the cell.
What is the Golgi Apparatus?
a stack of flattened membranes which modifies, sorts, and packages proteins and other materials from the endoplasmic reticulum for storage in the cell or release outside the cell.
How do proteins get from the Endoplasmic Reticulum to the Golgi Apparatus?
Newly assembled proteins are carried from the Endoplasmic Reticulum to the Golgi Apparatus inside of a membrane enclosed bubble called a “vesicle” which has tiny molecular “address tags” on the outside of the membrane.
What are Ribosomes?
small particles of RNA and protein found throughout the cytoplasm of a cell (and on the surface of rough endoplasmic reticulum) which receive instructions to make a protein from mRNA and chemically combine specific amino acids into longer chains (polypeptides).
What is the function of a chloroplast?
(““Chloro” = green) Chloroplasts capture the energy from sunlight and convert it into food that contains chemical energy in a process called photosynthesis.
What is the function of a mitochondria?
(“mitos” = “thread”) (“khondros” = “granule”) mitochondria convert chemical energy stored in food into compounds that are more convenient for the cell to use.
What is the function of the cell membrane?
the cell membrane regulates what enters and leaves the cell and also helps protect and support it.
What is a cell membrane made of?
a phospholipid bilayer.
(“Phospho” = phosphorous groups)
(“Lipo” = fat)
(“Bi” = two)
So, it is a double layer of phosphoric heads which are attracted to water (hydrophilic) and fatty acid tails which repel water (hydrophobic).
("Hydryo" = water)
("Phil(ia)" = attraction for)
("Phob(ic) = scared of)
