What is the gap between the proteins called? …
Channel
acts like a gate; when the hormone (insulin) binds with the protein, it acts like a key that opens the locked gate, allowing the glucose (sugar) t pass through.
What is the gap between the proteins called in a cell membrane?
Figure 5.
A gap junction
is a protein-lined pore that allows water and small molecules to pass between adjacent animal cells. Gap junctions develop when a set of six proteins (called connexins) in the plasma membrane arrange themselves in an elongated donut-like configuration called a connexon.
What types of molecules attach to the protein?
We see in Chapter 10 that proteins are often anchored to cell membranes through
covalently attached lipid molecules
. And membrane proteins exposed on the surface of the cell, as well as proteins secreted outside the cell, are often modified by the covalent addition of sugars and oligosaccharides.
What is the difference between the position of surface proteins and membrane-spanning proteins?
What is the difference between the position of the surface proteins and the membrane-spanning proteins?
Surface proteins do not span the cell membrane
. … Far fewer small molecules inside compared to outside cell. Concentration of small molecules greater outside compared to inside.
What part of the cell membrane is shown in more detail in Model 3?
Which part of the cell membrane is shown in more detail in Model 3?
Membrane-spanning proteins
(These are often referred to as channel proteins later in the activity.)
Do channel proteins use energy?
Energy is not required
because the particles move along the concentration gradient, or the difference between the high concentration of particles outside the membrane and the low concentration of the particles inside.
Does facilitated diffusion require ATP?
Simple diffusion does not require energy:
facilitated diffusion requires a source of ATP
. Simple diffusion can only move material in the direction of a concentration gradient; facilitated diffusion moves materials with and against a concentration gradient.
What are channel proteins?
A channel protein,
a type of transport protein
, acts like a pore in the membrane that lets water molecules or small ions through quickly. Water channel proteins (aquaporins) allow water to diffuse across the membrane at a very fast rate. Ion channel proteins allow ions to diffuse across the membrane.
How do proteins get their shape?
The primary structure of a protein — its amino acid sequence — drives
the folding and intramolecular bonding of the linear amino acid chain
, which ultimately determines the protein’s unique three-dimensional shape. … Folded proteins are stabilized by thousands of noncovalent bonds between amino acids.
What are examples of proteins?
- lean meats – beef, lamb, veal, pork, kangaroo.
- poultry – chicken, turkey, duck, emu, goose, bush birds.
- fish and seafood – fish, prawns, crab, lobster, mussels, oysters, scallops, clams.
- eggs.
- dairy products – milk, yoghurt (especially Greek yoghurt), cheese (especially cottage cheese)
Why is a protein channel called a gated channel?
Why is the protein channel in Model 3 called a “gated” channel?
Channel acts like a gate
; when the hormone (insulin) binds with the protein, it acts like a key that opens the locked gate, allowing the glucose (sugar) t pass through.
What facilitates diffusion?
Membrane proteins such as carriers and channels
facilitate the movement of molecules across the plasma membrane. … For instance, facilitated diffusion by channel proteins (e.g. transmembrane channels) is one that uses membrane proteins that act like a pore in the lipid bilayer.
What is called diffusion?
Diffusion is
the movement of a substance from an area of high concentration to an area of lower concentration
. Diffusion occurs in liquids and gases when their particles collide randomly and spread out. Diffusion is an important process for living things – it is how substances move in and out of cells.
Why would water and the solute move?
The mechanism responsible for driving
osmosis
has commonly been represented in biology and chemistry texts as either the dilution of water by solute (resulting in lower concentration of water on the higher solute concentration side of the membrane and therefore a diffusion of water along a concentration gradient) or by …
What are two substances that would need to move into a cell to maintain homeostasis?
Homeostasis depends on maintaining correct fluid levels within the cell and on exchanging useable materials, such as
oxygen
, for waste products, such as carbon dioxide. Plasma membranes allow water, oxygen and carbon dioxide to pass through by osmosis, or passive diffusion.
What does it mean that the plasma membrane is selectively permeable?
Selective permeability of the cell membrane refers
to its ability to differentiate between different types of molecules, only allowing some molecules through while blocking others
.
