Chapter 1 - INTRO Flashcards
Which six elements account for the major weight of most organisms?
Hydrogen, carbon, nitrogen, oxygen, phosphorus and sulfur.
Give the structure building blocks of proteins, DNAs and RNAs.
Proteins are made up of amino acids: contain an amino group, a carboxyl group, a side chain, and a hydrogen atom attached to a central carbon atom
DNA is composed of nucleotides: a sugar (deoxyribose), a phosphate group, and a nitrogenous base.
RNA is also made up of nucleotides, but it contains sugar ribose instead of deoxyribose.
What are polysaccharides? Use what linkage?
Monosaccharides connected by a glycosidic bond; acetal linkage
Nucleotides are…
functional monomers used to prepare nucleic acid polymers.
Each nucleotide contains 3 things:
5 carbon sugar, heterocyclic containing nitrogen base, and at least one phosphate group.
Lipids are either _____ or contain significant nonpolar regions. This monomer is less ________. The simplest form are __________. The ____________ area major component of biological membranes.
nonpolar; systematic; fatty acids (FAs); Glycerophospholipids
What are the 2 common types of nucleic acids? How are nucleotides connected?
DNA and RNA; via 3’,5’-phosphodiester bonds
What does metabolism describe?
The synthesis/degradation of biomolecules coupled with the energy transferred, stored, & used (bioenergetics).
Energy transfer is both related to both ______ (rates) and _______ (spontaneity)
kinetics; thermodynamics
If delta G<0, the reaction is ________. If delta G=0, the reaction is _______. If delta G>0, the reaction is ______.
spontaneous; at equilibrium; nonspontaneous
What does delta G++ represent?
The activation barrier (Ea)
Cell are all classified as either _______ or _________. The membrane is __________. The cytoplasm describes everything enclosed by the plasma membrane including: _______ and _________.
prokaryotes; eukaryotes; semi-impermeable; organelles; cytosol
Prokaryotes are usually ________ organisms. List 4 things and give an ex.
single-celled; don’t have a nucleus regions but instead a nucleoid region, usually no internal membrane compartments, often have pili/flagella, high SA to volume ratio (easier to transport/traffic via simple diffusion); Escherichia coli
List 4 things about eukaryotic cells.
Have a single plasma membrane and a nucleus, much smaller SA to volume ratio (need mechanisms for active transport), most contain organelles, multicellular eukaryotes have differentiated cells/tissues
What is the nucelus?
A large membrane-enclosed region present in most eukaryotic cells that serves as its control center.
What is the nuclear envelope?
Is a double lipid bilayer, provides extra protection/security.
Each linear nucleic acid sequence is called a _________. Most eukaryotes are ____ and contain two copies of each chromosome. Sex cells are ____ and contain one copy of each chromosome.
chromosome; diploid; haploid
What serves as the location for DNA replication, RNA transcription and is highly regulated?
The nucleus.
Describe the Endoplasmic reticulum (ER).
A network of membrane-enclosed folds which radiate outward from the nucleus.
Where are ribosomes located in the ER? And what is their role?
The exterior surface; synthesize proteins from mRNA (translation).
What is the lumen and their role?
The interior of the ER; collects/organizes proteins for cellular export via vesicles.
What happens to the vesicles when the are exported from the ER?
They arrive at the Golgi apparatus, modified, reorganized, & packaged for transport (out of cell or other locations)
What 2 things are involved in energy transduction?
Mitochondria and chloroplasts
Name similarities b/w the mitochondria and chloroplasts.
Contain a double-membrane (inner, outer), inner membranes are highly-folded…increasing SA, inner membranes and their interior regions are critical for organelle function, both derived from ancient bacteria
Define a vesicle.
A specialized, single membrane-enclosed region within a cell.
What protects the cytosol?
Compartmentalization.
Where are lysosomes found and their function and how.
Found in eukaryotic cells and used for cellular digestion; interior is highly acidic and contains many enzymes to break down macromolecules.
What are Peroxisomes found and used for?
Found in animal (and some plant) cells and used to conduct oxidation reactions with H2O2.
Where are Vacuoles found and their function?
Found in mature plant cells (and some protists) and used for storage.
Is the cytoskeleton an organelle?
No
CYTOSKELETON: What are the 3 types of protein filaments?
Actin filaments (microfilaments), Microtubules, Intermediate filaments.
State something about actin filaments.
Most abundant protein in a cell.
State 2 things about microtubules.
Thicker, stronger fibers of tubulin, packed in bundles. Serve as an internal skeleton and for directed movement (e.g. cilia).
State 1 thing about Intermediate filaments.
Extend outward from nuclear envelope to help cell resist external stress.
