Atoms and Water
How many electrons and protons will be around an atom's nucleus if the atomic number is 15?
15 and 15
What are anabolic and catabolic reactions?
Anabolic requires energy to synthesize or build more complex molecules
Catabolic deconstructs complex molecules into smaller ones, releasing energy
What does the fluid mosaic model consist of?
Phospholipids, cholesterol, proteins, carbohydrates
Along what concentration gradient does diffusion occur?
High areas of concentration to low areas of concentration.
Differentiate between hydrogen, covalent, and ionic bonds.
Ionic: stealing electrons
Covalent: share electrons
Hydrogen: weak attraction (O-H, F-H, N-H)
How many neutrons will an element have if there are 50 protons and the atomic mass is 500?
450 neutrons 500-50 = 450
What is the difference between condensation and hydrolysis?
Condensation is the synthesis of two molecules and hydrolysis is the splitting of two molecules with water.
The fluid mosaic model is a bilayer. What does that mean?
There are two row of phospholipids tightly packed.
If a molecule has a low rate of permeability what may it need to cross the plasma membrane?
membrane proteins and channels
Draw two bonded nucleotides.
sugar phosphate backbone (phosphate head, pentose sugar base (deoxyribose or ribose)), nitrogenous base
Bonded between the phosphate group and the 3' hydroxyl group of the sugar on the next nucleotides
Describe the basic structure of an atom.
A dense, positively charged nucleus at the center with protons and neutrons surrounded by a negative electron cloud.
Draw the functional group carboxyl.
Carbon double bonding to oxygen and single bonded to a hydroxyl
What holds the two layers together?
Amphipathic attractions between hydrophobic and hydrophilic parts of the phospholipids.
Which molecules can cross the plasma membrane, which cannot and why? What is the term for this?
can:
small, nonpolar molecules (hydrophobic fatty acid tails of phospholipids)
cannot: (interior of membrane is hydrophobic repelling all of those below)
large, uncharged polar molecules, small ions, small uncharged polar molecules
selectively permeable
Which type of lipid has the most kinks and what result does that have?
Unsaturated fatty acids
Higher permeability, kinks create room for substances to move with less restriction
How do subatomic particles predict the properties of an atom?
The number of protons in the nucleus is the atomic number, neutrons contribute to atomic mass and create various isotopes, electrons decide the reactivity and interaction.
What are examples of a disaccharide?
Maltose, cellobiose, lactose, sucrose
What are some functions of proteins in the plasma membrane?
channels for molecule transport, receptors for cell signaling, anchor the membrane
What is the difference between passive and active transport?
Passive does not require energy, such as diffusion and osmosis
Active requires energy like ATP to move substances against the concentration gradient
What type of tonicity for an eye drop solution be used for a swollen cornea?
Hypertonic to draw fluid from the eye.
What two types of bonds does water have when bonding and where are they?
O-H connecting multiple water molecules: hydrogen
What is glycogen used for and what kind of carbohydrate is it?
Energy storage in animals
Polysaccharide
What is the role of cholesterol in the membrane?
Increases the packing density of phospholipid tails
Makes it harder for small molecules to pass through
Damps the temperature effects on the membrane (increases fluidity at low temp. and decreases it at high temp. to prevent it from becoming to rigid or too fluid)
Which of the following best described facilitated diffusion?
a) movement of molecules against the concentration gradient using energy
b) movement of water molecules through a semipermeable membrane
c) bulk transport of materials into the cell via vesicles
d) passive transport of molecules across a membrane via specific transport proteins
What are the two structures for the secondary level of protein strucutre?
alpha helix
beta pleated sheet