AP Biology Unit 1

The partial negative charge in a molecule of water occurs because

the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom nucleus than around the hydrogen atom nucleus

How many times greater is the pH 9 to pH 5

10000 times greater

Rank the following by pH lowest to highest: urine, blood, and stomach acid

stomach acid, urine, blood

the polarity of a water molecule..

allows the oxygen of one water molecule to bond weakly to the hydrogen of another water molecule

Hydrogen bond is when there is

attraction between the partial positive charge on the hydrogen atom and the partial negative charge on an electronegative atom 

In a polar covalent bond…

is when two atoms are bonded with two different electronegativity

How many molecules of water are released during the polymerization of 50 monomer-long cellulose molecule

49

Why can humans digest starch but not cellulose?

This is because humans have enzymes that can hydrolyze the a-glycosidic linkages of starch but not the b-glycosidic linkages of cellulose

What is used to form a nucleotide

a pentose sugar, a phosphate group, and a nitrogenous base

A central carbon atom in an amino acid is bonded to

an amino functional group, a carboxyl functional group, a side chain, and hydrogen.

Lipids are diverse compounds that are grouped together because they are

hydrophobic

A fat molecule is composed of two types of smaller molecules

glycerol and fatty acids

A fatty acid consists of a

carboxyl group and a long hydrocarbon chain

_____________ have on or more double bonds in their hydrocarbon chains are usually found in vegetable oils

unsaturated fatty acids

The hydrocarbon chains of ________ are not kinked, and thus pack closely together, making animal fats solid at room temperature

saturated fatty acids

___________ are a major component of cell membranes. They form a bilayer with their hydrophobic tails mingling together and their hydrophilic heads facing the watery environment on both sides of the membrane.

Phospholipids

___________ are lipids with a structure consisting of four fused rings. Many sex hormones are made from this type of lipid

Steroids

Nitrogenous bases

adenine, guanine, cytosine, thymine(DNA), uracil(RNA)

DNA

stores genetic info, codes for seq. of amino acids in proteins

RNA

store genetic info in viruses

How many bonds are bonding Cytosine and guanine and where it is found. Mention the stability

3 hydrogen bonds, found in both DNA and RNA and is more stable

How many bonds are bonding Adenine and Thymine, where is it found, mention the stability

2 hydrogen bonds, found only in DNA, and is less stable

How many bonds are bonding Adenine and Uracil, where is it found, mention the stability

2 hydrogen bonds, found only in RNA, is less stable

Which end are new nucleotides added to polynucleotides

3’ hydrogen end

Which bonds are found in polynucleotides

phosphodiester linkages

Monomer of nucleic acids

nucleotides

polymer of nucleic acids

polynucleotides

monomers of lipids

glycerol and fatty acids

polymers of lipids

lipids do not have polymers

Elements used in lipids

Carbon, hydrogen, Oxygen, and sometimes Phosphorus, Nitrogen, Sulfur

triglycerides are

lipids, nonpolar fats and oils. They are used for long term energy storage. Saturated fat is solid at room temp, in animal fat. Unsaturated fats are liquid, in plant oil. All triglycerides have ester linkages

steroids have

4 fused carbon rings, are nonpolar, are used for sex hormones. Cholesterol is a steroid and is a component of animal cell membranes.

Phospholipids have

hydrophilic polar head (group and glycerol) and hydrophobic nonpolar tails (2 fatty acids). Are used as a primary component of all cell membranes

Types of proteins

amino acids and polypeptides. They catalyze chemical reactions (enzymes). Cell transport proteins, defense(antibodies), cell signaling (receptors), movement (motor proteins), structural (keratin, collagen, cytoskeleton)

Interactions between R-groups

ionic bonds, hydrogen bonding, hydrophobic interactions, covalent bond (disulfide bridges)

monomers of proteins

amino acids

polymer of proteins

polypeptides

monomers of carbohydrates

monosaccharides(simple sugars)

polymers of carbohydrates

polysaccharaides

bonds in polysaccharides

glychosidic linkages

Structural polysaccharides

cellulose (plant cell walls) and chitin (exoskeleton)

Energy storage polysaccharides

starch(plants) and glycogen(animals)

Nitrogenous bases: pyrimidines

one ring with 6 atoms

Nitrogenous bases: purines

one ring with 6 atoms bonded to one ring with 5 atoms

Identify the elements that make up nearly all living matter

CHOPN

Describe ionic bonds

Ionic bonds help transfer electrons from metals to nonmetals

How are hydrogen bonds different from other types of bonds

they are different because there is an intermolecular bond that forms between molecules

Cohesion

water attracts to water, responsible for surface tension

Capillary action

There is a greater adhesion than cohesion and there is upward movement of water