Exam (elaborations)
BIO 348 Chapter 11: membrane structure Questions with Correct Answers
- Course
- Institution
BIO 348 Chapter 11: membrane structure Questions with Correct Answers
[Show more]
Content preview
BIO 348 Chapter 11: membrane structure Questionswith Correct Answers
membrane functions Correct Answer--Barrier separating what's inside of
a cell from what's outside
-Selectively allows substances enter (e.g. nutrients) or leave (e.g. wastes)
the cell (through transport proteins)
-Compartmentalization within the cell (organellar membranes)
-Allows cell to sense and respond to external environment (receptor
proteins)
-Changes shape in response to cell needs (i.e. cell needs to grow or
change shape)
Internal cellular membranes Correct Answer--Eukaryotic cells contain
several of these that aid in surrounding and enclosing the various
organelles
-have essentially the same functions as PM
Selective barrier, etc.
membrane composition Correct Answer--fluid mosaic model
-lipid bilayer
-contain a combination of lipids and proteins
*phospholipids
*cholesterol
*glycolipids
*glycoproteins
,fluid mosaic model Correct Answer-model that describes the
arrangement and movement of the molecules that make up a cell
membrane (it moves around, contains different things)
Lipids and proteins present in the membrane Correct Answer-
Phospholipids
Cholesterol
Glycolipids
Glycoproteins
head of phospholipid Correct Answer-polar, hydrophilic
tail of phospholipid Correct Answer-nonpolar, hydrophobic
proteins of membrane Correct Answer-serve as channels
membranes are phospholipids composed of Correct Answer-
phospholipids
phospholipids are made of Correct Answer-glycerol, two fatty acids and
a "head" containing phosphate
Phospholipids are Correct Answer-amphipathic (hydrophobic and
hydrophilic)
, phospholipids spontaneously form Correct Answer-ilayers when placed
in aqueous environment (protects hydrophobic tails from water)
Phosphatidylcholine Correct Answer-Common phospholipid present in
abundance in most cell membranes; uses choline attached to a phosphate
as its head group.
*look at image**
amphipathetic components Correct Answer-Phospholipids, Glycolipids
and Sterols (cholesterol)
-look at image**
energetics of membrane function Correct Answer--When amphipathic
molecules are placed in an aqueous environment, the hydrophilic portion
wants to interact and dissolve in water, whereas the hydrophobic
portions want to avoid water
-The solution (for phospholipids): the lipid bilayer! Hydrophobic tails
hang out with each other, hydrophilic heads are oriented towards the
aqueous solutions
-Any edges are going to be energetically unfavorable (why?)
-Therefore, lipid bilayers automatically seal themselves to avoid edges
-Membranes are self-repairable, if there is a damaged end, they
automatically self-seal
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller cracker. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
78252 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now