Explain membrane permeability, Biology

Assignment Help:

A pure  phospholipid  bilayer with  its  hydrophobic  interior,  is permeable  to water and gases such as O2, CO2, N2 and small uncharged  polar molecules such as urea, ethanol, but is impermeable  to large uncharged polar molecules such as glucose, ions (Na+   , K+   , Cl-, Ca2+   ) and charged polar molecules instance for amino acids, ATP, glucose  6-phosphate. The initial group of molecules  can cross a biological membrane  unaided  and without  an input  of energy,  whereas  the latter group requires  the  presence  of  integral  membrane  transport  proteins  and,  in  many cases   an   input   of   energy   to   travel   by   the   otherwise   impermeable membrane  barrier.  Thus the plasma membrane and the membranes of internal organelles are selectively permeable barriers and maintaining a distinct internal environment.

 


Related Discussions:- Explain membrane permeability

Respiration, abnormal lung volumes and capacities

abnormal lung volumes and capacities

Explain protein deficiencies in nutritional care, Explain Protein Deficienc...

Explain Protein Deficiencies in Nutritional Care? A depleted amino acid pool leads to poor wound healing (dehiscence), delayed healing of fractures, anaemia, depressed pulmonar

Defina about the lipid metabolism, Defina about the Lipid Metabolism? A...

Defina about the Lipid Metabolism? Animal studies consistently show a hypotriglyceridenlic effect although equivocal results have been seen with healthy humans. Hypotriglycerid

Which kind of circulatory system do molluscs have, Q. Which kind of circula...

Q. Which kind of circulatory system do molluscs have? How can it be compared to the respiratory system of annelids? Molluscs, with the exception of cephalopods, have an open ci

Removal of a patient''s peripheral intravenous catheter, Removal of a patie...

Removal of a patient's peripheral intravenous catheter resulted in brief bleeding and the loss of a small amount of blood. Which of the following processes occurred during the form

Carbohydrates requirement in pectic ulcer, Q. Carbohydrates requirement in ...

Q. Carbohydrates requirement in pectic ulcer? Carbohydrates: These should provide around 55 to 65% of the daily intake. Emphasis - J should be laid on the consumption of 60th s

Prophase, Prophase This is the first and longest phase of mitosis .At i...

Prophase This is the first and longest phase of mitosis .At its beginning  all  10 nm segments   of chromatids (= chromonemata)  of the  duplicated  chromatin fibres of interph

What are non-threshold approaches, Non-threshold  approaches For  gene...

Non-threshold  approaches For  genetic carcinogenes, the  "NOEL-safety factor"  approach  is generally  not considered a suitable method for setting the acceptable intake level

Oxygen stratification - lake ecosystem, Oxygen Stratification - Lake Ecosys...

Oxygen Stratification - Lake Ecosystem In most lakes, oxygen stratification nearly parallels that of temperature during the summer season. The amount of oxygen is greatest on

Type of genetic inheritance that determines abo blood group, What is the ty...

What is the type of genetic inheritance that determines the ABO blood group system? What are the relations of dominance among the involved alleles? The inheritance of the ABO b

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd