Organelles and General Processes Flashcards
What does DNA do when it is inside the nucleus of a non dividing cell? What is it called?
DNA gathers around proteins, DNA in this state are chromatin.
The Nucleus contains what substance and what structure houses it?
DNA, Nuclear Envelope
What is DNA referred to when a cell is dividing? How many of these structures are present in humans?
Chromosomes; 46
Generally what is the function of DNA?
Contains instructions to build protein molecules that do the work of the cell.
Does the function of organisms rely on DNA? Why?
Yes, proteins created with the instruction of DNA allow the cell to function, organisms rely on the proper functioning of cells.
Scientists have demonstrated the centrality of DNA to cell function by doing what experiment?
Scientists have injected the nucleus of one organisms cell into the cytoplasm of a another organisms cell. That cell in turn started to produce proteins specific to the DNA of the original organism.
What are Ribosomes?
Small structures found within cytoplasm.
DNA is copied by what molecule when making proteins?
messenger RNA (mRNA)
What is the function of Ribosomes in the formation of proteins in cells?
Ribosomes organize mRNA and needed materials for protein creation.
What is endoplasmic reticulum? What kinds of Endoplasmic Reticulum exist? What characteristics separate them?
Endoplasmic Reticulum is a series of canals that connect the nucleus to the cytoplasm. Two types exist: Rough ER and Smooth ER. RER has ribosomes that attach to it during protein production. SER does not.
Rough Endoplasmic Reticulum (RER) makes proteins that are used for what purposes?
the cell membrane, or proteins that leave the cell
What does the Smooth Endoplasmic Reticulum produce?
lipids that are moved to the Golgi Apparatus.
What is the location of the Golgi Apparatus? What surrounds the Golgi Apparatus?
GA is located near the ER and is surrounded by transport vesicles.
What occurs inside of the Golgi Apparatus?
molecules produced by the cell are chemically tagged and moved out. lysosomes are produced.
What is the function of Lysosomes?
digestive enzymes that remove harmful elements and dead organelles.
What are functions of Peroxisomes?
remove cell toxins like hydrogen peroxide by turning it into water and oxygen
What is the function of mitochondria?
Breaks down food for cell use and moves it to storage in the form of ATP (adenosine triphosphate).
What is the process of breaking down food in the mitochondria called?
cellular respiration
What are enzymes? What is their general purpose?
properly folded proteins, acting as catalysts for needed chemical reactions
Why are enzymes so important?
without enzymes to act as catalysts a pathway does not form resulting in a lack of a needed substance
Give an example of an enzyme and what results when it acts as a catalyst?
urease catalyzes the reaction between urea and water resulting in ammonia and carbon dioxide
Describe a reaction in which urease acts as a catalyst?
the reactants form bonds (water and urea) then break apart forming ammonia and carbon dioxide leaving urease unchanged
More specifically what does an enzyme do?
reduces energy requirements for reactions making them more likely, enzymes do not add energy to a reaction
What is a cofactor? Give some examples of cofactors.
a cofactor is an inorganic molecule which aid enzymes
zinc, potassium, iron are all cofactors