The temperature at which a membrane solidifies depends on its fatty acid composition. A membrane rich in unsaturated tails will remain fluid to a lower temperature. How are the proteins attached to cell membrane via lipids? They are attached through lipid-anchored cell membrane proteins. They are attached through myristoylation, palmitoylation, or isoprenylation.
Describe the activity of sodium and potassium ion channels. Pores are ion-specific and provide free access to their respective ions across the plasma membrane. Ions move through these pathways via diffusion – down their concentration gradient. 6. How do the
A) is neutralized by water B) is surrounded by water molecules C) reacts and forms a covalent bond to water D) aggregates with other molecules or ions to form a micelle in water Answer: B Page Ref: Section 3 11 9) Which would you expect to be most soluble in water? A) I B) II C) III D) IV Answer: A Page Ref: Section 3 10) Solutes diffuse more slowly in cytoplasm than in water because of A) the higher viscosity of water. B) the higher heat of vaporization of water. C) the presence of many crowded molecules in the cytoplasm. D) the absence of charged molecules inside cells.
| | | A) | cytoskeleton | | | B) | fluid mosaic model | | | C) | impermeable membrane | | | D) | genetic material | | | | | | Feedback: Phospholipids in the plasma membrane create a fluid environment in which other molecules can float, allowing selective permeability. This is known as the fluid mosaic model. | | 13 CORRECT | | What effect has eukaryotic evolution had on cells? | | | A) | more simplified structures | | | B) | greater adaptability
The dissolving process involves a consideration of the relative strength of three intermolecular attractive forces. The type of forces between solute-solute molecules and solvent-solvent molecules must be considered. These intermolecular attractions must be broken before new solute-solvent attractive forces can become effective. A solute will dissolve in a solvent
P2 Outline the Main Tissues Of The Body Epithelial Epithelial tissue is basically the linings of both the internal and external surfaces of the body and can be divided into two groups. The groups depend upon the number of layers of which it is composed. These two groups are simple epithelial and compound. Simple squamous are thin, flat plates and their main function is osmosis (which is the passage of water molecules from a region of low concentration to one of high concentration through a semi-permeable membrane) and diffusion (which is the passage of molecules from a high concentration to a low concentration). They form the lining of cavities such as the mouth, blood capillaries, heart and lung alveoli and make up the outer layers of the skin.
CHAPTER 5: MICROIAL METABOLISM PRE-TEST 1: Which of the following types of transport involves the expenditure of energy and special membrane proteins? ACTIVE TRANSPORT 2: Which of the following molecules serves as the short-term recyclable energy supply for a cell? ATP 3: Which of the following is a waxy lipid found predominantly in the cell walls of Mycobacterium? MYCOLIC ACID 4: Catabolic reactions are chemical reactions that BREAK LARGE MOLECULES APART 5: Denaturation is typically a problem with which of the following? PROTEINS 6: A difference in the concentration of a chemical on both sides of a membrane leads to which of the following phenomena?
Glucose travels in the plasma or liquid part of your blood but cholesterol (triglycerides) travel bound to protein carriers in the blood. Based on their respective chemical properties, explain the reason for this difference. (2 marks) Cholesterol is an amphipathic molecule, since it has polar and non – polar regions. Even though the cholesterol has polar group (OH) it dissolves fats than in aqueous
What is the difference between prokaryotic cells and eukaryotic cells? What are the names for the two major groups of prokaryotes? both have a cell membrance on the outside and both have ribosomes but the eucaryotic only have membrane bound organelles. both can have the cell wal. euc.