Bio 156 Chapter 5A, part 2

ATP, ADP, AMP

ATP (3 phosphate) when used is broken down into ADP+P (2 phosphate), and so forth with AMP

isotonic

An isotonic solution is one in which the concentration of solutes is the same both inside and outside of the cell

Diffusion

Diffusion is the movement of particles down their concentration gradient.

In this diagram of the plasma membranes of two adjoining cells, identify the protein indicated by the white arrow, including its function

a receptor protein that binds with a signaling molecule and relays the message into the cell by activating other molecules inside the cell. Signaling proteins are part of signal transduction pathways that transmit external chemical signals into the cell.

Passive Transport

down a concentration gradient, no input of energy. simple diffusion (hydrophobic) osmosis facilitated diffusion: (hydrophilic)

hypotonic

has a lower concentration of solutes outside the cell than inside the cell. In an attempt to balance the concentrations of solutes inside and outside the cell, water will rush into the cell, and can cause it to burst.

Plasma Membrane Structure

phospholipid bilayer: hydrophobic center, hydrophilic exterior. cholesterol makes membrane less deformable. proteins: integral vs. peripheral carbohydrates: short, branched chains of sugars. cell-cell recognition. glycolipids vs. glycoproteins

Osmosis

simple diffusion of water across a semi-permeable membrane. dependent on the number of solute particles present

Structure A is a _____.

solute

hypertonic

the concentration of solutes is greater outside the cell than inside it. causes the cell to become dehydrated and shriveled

Structure B is a _____.

transport protein

Facilitated Diffusion

use of integral proteins to transport hydrophilic substances 1. carrier-mediated (aminos) 2. channel-mediated (ions usually, water) and protein helper