Natural Selection
What are genes?
Are the mechanism for both variation and inheritance.
what are atoms?
The smallest individual units that have properties of an element.
What is an element?
Atoms that have their own special properties based on the number of protons, neutrons, and electrons.
proteins
lipids
carbohydrates
nucleic acids
what is an enzyme?
protein that facilitate the chemical reactions needed for cellular work.
where does variation come from?
Our variation comes from the genes that we pass on to our offspring. We pass on a genotype that codes for a specific phenotype (trait).
what are ions?
charged atoms.
Name the subatomic particles that make up an element.
Protons-(+ charge) determines the element and is located inside the nucleus
Neutrons-(no charge) determines the isotope of the element and is located in the nucleus
Electrons-(- charge) forms a negative cloud around the nucleus and determines the chemical behavior of the element
What is a monomer? what is a polymer?
Monomers are the smaller molecules that make up macromolecules and is bonded by covalent bonds.
A polymer is a chain of monomers and is bonded by the dehydration reaction.
what makes up an enzyme?
Enzymes work by forming a binding site for a molecule. The binding site is a pocket with specific amino acid residues called active sites.
1. Stabilizing selection
2. directional selection
3. diversifying selection
what is an ionic compound?
the transfer/donation of an electron
What is the octet rule?
atoms will gain or lose electrons to attain the most stable electron shell configuration.
What are carbohydrates made of?
Made of polymers called polysaccharides made from a subunit monomers called monosaccharides.
what is the molecule that binds into the active site?
the substrate
What are mutations?
Mutations are random changes in the gene that can be harmful, beneficial, or neutral.
what is a covalent bond?
atoms that share electrons which results in each atom gaining a completed valence shell.
1st energy level holds 2 electrons
2nd energy level holds 8 electrons
3rd energy level holds up to 8 electrons
what are proteins made of?
polymers called polypeptides which are made up of monomer subunits called amino acids.
why do substrates need enzymes?
To lower the energy of activation of reactions by making the transition state more stable.
What are the two observations and inferences that Darwin stated for natural selection?
Observation 1: variation exists among individuals in populations.
Observations 2: Overproduction of offspring.
Inference 1: Unequal reproductive success. Individuals who are better suited for their environment will be more successful and produce more offspring.
Inference 2: Accumulation of favorable traits over time.
what are the two types of covalent bonds?
non-polar covalent bond- equal sharing of electrons between atoms
polar covalent bond- unequal sharing of electrons between atoms
What is electronegativity?
How much an atom wants or pulls electrons. The higher the electronegativity difference of two atoms the more ionic a bond is and if the difference is low it is polar covalent.
What are considered lipids?
Lipids are a diverse group made up of fats, phospholipids, waxes, and sterols.
How are enzymes regulated?
Molecules bind to enzymes to induce a structural change that either increases or decreases activity.