Module 2 Flashcards
(31 cards)
What kind of barrier is the cell membrane
Selectively permeable barrier
Simple diffusion
Molecules move directly through the phospholipid bilayer of the cell membrane without help
Facilitated diffusion
Larger molecules like glucose or ions cannot pass through on their own because they are to big and need help and use specialize channels of carrier proteins to help them get across
What is osmosis crucial for?
Maintain cell function.
- if unregulated water movement can result in cell swelling or shrinking
Tonicity
A solutions ability to influence water movement across the membrane its closely linked to osmosis. Tonicity is determined by the Osimilarity of the solution relative to the cell
Hypotonic solution
If a cell is put in this solution that means the inside of the cell is more concentrated and water will cross into the cell causing it to swell
Hypertonic solution
If cell is put into this solution it means the solution is more concentrated and water will leave the cell causing to it shrivel up
Isotonic solution
If a cell is put into this solution, the inside of the cell and liquid out side are balanced which means the water will flow back and forth
What is the transport method of small molecules
Simple diffusion: small enough to slip through the cracks (phospholipids)
Example of small molecules
Oxygen, carbon dioxide
What is the transport method of large molecules?
Channel mediated or carrier mediated transport
Example of large molecules
Glucose, amino acids
The role of electrostatic forces
Charge molecules like sodium cannot pass through the membrane because they repel the hydrophobic interior. So they require specialized channels to help them cross the membrane. Sodium enters the cell through voltage gated ion channels during their signaling. They also have an electrochemical gradient as well as a concentration gradient.
What is hydrophobic
Lipid soluble ur fad soluble
What is hydrophilic
Water soluble
If you have a phospholipid membrane is the core hydrophobic or hydrophilic
Hydrophobic
What transport method will substances like steroids and fatty acids use
Since the cell has a phospholipid layer they can ease enter with since it is hydrophobic meaning its passive transport or simple diffusion
What is an example of passive transport?
. Simple diffusion
Explain initiation for mRNA
RNA polymerase is signaled to begin transcribing a gene. And piñas to the mRNA to a point called the promoter
Explain elongation in mRNA
Once the RNA polymerase is bonded it starts to unwind the DNA double helixas it reads The DNA the RNA polymerase builds a strand of mRNA this step continues as it elongates the strand
Explain termination with mRNA
RNA polymerase continues until it reaches a termination sequence which is a certain set of heuciotides signaling its the end of a gene.
What is pre-mrna
mRNA that requires several modifications before it can be used for translation.
Initiation in making enzyme chain
mRNA binds to the small part of the ribosome.a tRNA that matches the sequence of the mRNA and carries the correct amino acid pears in formed together. Then the large part of the ribosome creates the chain of amino acids and spits them out
. Explain elongation with making peptide chain.
The ribosome moves along the mRNA reading the bases attaching the corresponding tRNA based on the codon. For each code on red, a peptide bond between amino acids is formed.
