section quiz 2 Flashcards
(39 cards)
What are the 2 types of Nucleic Acids?
DNA and RNA
What does a nucleotide contain?
a phosphate group, a sugar molecule, and a nitrogen-containing base
The information in a molecule of DNA is determined by what?
Its sequence of bases (Adenine, guanine, cytosine, and thymine)
In DNA, what pairs with what?
A & T and G & C
Difference between RNA and DNA?
Instead of thymine, RNA has a similar base called uracil
Define cell
the smallest unit of life that can function independently and perform all the necessary functions of life, including reproducing itself
What are the 2 main categories of cells?
Eukaryotic cells and Prokaryotic cells
What does the cell theory state?
All living organisms are made up of one or more cells and that all cells arise from one another
Endosymbiosis theory
developed to explain the presence of two organelles in eukaryotes, chloroplasts in plants and algae, and mitochondria in plants and animals
What determines whether a protein resides on the surface or extends through the bilayer?
Amino acids may contain either hydrophobic or hydrophilic side chains
What are the 4 primary types of membrane proteins that perform different functions?
Receptor, recognition, transport, and enzymatic proteins
Why do “beta blockers” reduce anxiety?
They work to dampen down the body’s ‘fight-or-flight’ response
What are the two types of passive transport:
diffusion and osmosis
What is simple diffusion?
molecules pass directly through the plasma membrane without the assistance of another molecule
What is facilitated diffusion?
Molecules move across the plasma membrane with the help of a carrier molecule
What is osmosis?
A type of passive transport by which water diffuses across a membrane, in order to equalize the concentration of water inside and outside the cell.
Define Tonicity
the relative concentration of solutes outside of the cell relative to inside the cell
Define Tonicity
the relative concentration of solutes outside of the cell relative to inside the cell
What are the three types of endocytosis?
Phagocytosis, pinocytosis, and receptor-mediated endocytosis
What is exocytosis?
the method by which cells export products for use in another location
What is the nucleolus?
an area near the center of the nucleus where subunits of the ribosomes are assembled
What are lysosomes?
round, membrane-enclosed, acid-filled vesicles that function as garbage disposals
What is the endomembrane system?
system that - produces modifies molecules to be exported to other parts of the organism and breaks down toxic chemicals and cellular by-products
function of the rough er?
modifies proteins that will be shipped to other locations in the endomembrane system, the cell surface, or outside the cell
