Unit 2 - Cells, Tissues And Integumentary System Flashcards
List the general functions of the plasma membrane
PRSS
Physical isolation.
Regulation of exchange with the environment.
Sensitivity to the environment.
Structure support.
Identify the components that allow the plasma membrane to carry out its functions
LPC
Lipids (phospholipids and cholesterol)
Proteins
Carbonhydrates
What component of the plasma membrane is primarily responsible for the membrane to form a physical barrier between the cells internal and external environment?
Phospholipid bilayer (forms a physical barrier between the internal and external environment)
Which type of integral protein allows water, ions, and water-soluble solutes to pass through the plasma membrane?
Channel proteins (Spans the membrane and makes hydrophilic tunnels across it, allowing its target molecules to pass through it by diffusion)
Explain the difference between the cytoplasm and the cytosol
Cytosol is the fluid contained in the cell cytoplasm.
Cytoplasm is the entire content within the cell membrane.
What are the major differences between cytosol and extracellular fluid?
In contrast to extracellular fluid, cytosol has a high concentration of potassium ions and a low concentrations of sodium ions.
Identify the nonmembranous organelles, and cite a function of each.
CCRP
Cytoskeleton (serves as the cells skeleton)
Centrosome and centrioles
(serves to organise the microtubules and provide a structure to the cell
Ribosomes (serves by making proteins)
Proteasomes (degrades unneeded or damaged proteins by proteolysis)
Describe the content and structure of the nucleus
Nuclear envelope
Nucleoplasm
Chromatin
Nucleos
The nuclear membrane forms an envelope like structure around the nuclear contents and is commonly known as a nuclear envelope
What is a gene?
The basic physical and functional unit of heredity
Define gene activation
The process of activation of a gene so that it is expressed at a particular time.
Describe transcription and translation
Transcription is the process by which DNA is copied to RNA.
Translation is the process where RNA is used to produce proteins.
What processes would be affected by the lack of the enzyme RNA polymerase.
The lack of polymerase will cause one of the subunits of RNA to not be transcribed from DNA
What is meant by the term selectively permeable when referring to a plasma membrane?
It’s the ability to differentiate between different types of molecules, only allowing some through and blocking others
Define diffusion
The spreading of something more widely from high concentration region to low concentrations region
List five factors the influence the diffusion of substances in the body.
DITCE
Distance Ion and molecule size Temperature Concentration gradient Electrical forces
How would a decrease in the concentration of oxygen in the lungs affect the diffusion of oxygen in blood?
Diffusion into the cells increase
Define osmosis.
The spontaneous passage or diffusion of water or other solvents through a semipermeable membrane
What effect would such a solution have on the cells lining the nasal cavity, and why?
Cells would lose water, due to the salt solution being a hypertonic solution
Describe the process of carrier-mediated transport
It combines a chemical reaction with a diffusion process.
The concentration of hydrogen (H+) in the stomach contents during digestion rises to a higher level than in the cells lining the stomach, which transport process must be operating?
An active transport process
Describe endocytosis
A process by which cells absorb external material by engulfing it with the cell membrane
Describe exocytosis
The process by which cells move materials from within the cell into extracellular fluid
What is the process called whereby certain types of white blood cells engulf bacteria
Phagocytosis
What is the membrane potential of a cell, and in what is it express?
Electric potential differences across the interior and exterior of the cell
80mv to 40mv