bio189 exam 1

chapters 1-3

chemistry

all living things are made up of chemicals

atom

• fundamental unit of matter

• nucleus: protons and neutrons

• electrons on outer rings

elements that make up most of the mass of living things

N, C, H, O, P (SPONCH)

periodic table

arranged by atomic number (increasing)

isotope

same element, different atomic mass

ion

gains or loses electrons

chemical reaction

rearranging electrons outside the nucleus (outside)

nuclear reaction

changes to the protons and neutrons inside the nucleus (inside)

nonpolar (covalent) bond

• elections are shared equally

• backbone of DNA and proteins

polar (covalent) bond

• electrons shared unequally

• partial positive and negative poles

ionic bond

• transfers 1 or more electrons

• holds compounds together

hydrogen bond

• slightly positive and negative

• weak

• vital for DNA

electronegativity

how badly does an atom want/attract extra electrons

nonpolar electronegativity

identical/similar

polar electronegativity

moderate differences

ionic electronegativity

• very large difference

• ex: metal and nonmetal

relationship between the arrangement of the periodic table and electronegativity

• increases from right to left

• decreases top to bottom

cohesion

attraction between molecules of the same substance (surface tension)

adhesion

attraction between water moles and molecules of a different substance (water droplets on leaves)

solid

• packed tightly

• because of hydrogen bonds = packed less tightly than liquid

• orderly

liquid

• packed closely but loosely and fluid

• moving

gas

completely loose or spread apart

hydrophilic

• compounds interact w/ water

• polar or ionic

• dissolves, mixes, spreads

hydrophobic

• compounds do not interact w/ water

• nonpolar

• repels water, separates, forms

process of a solute dissolving in a solvent to form a solution

solute is being dissolved, solvent does the dissolving, solution = homogenous mix of 2 or more kinds of molecules (atoms or ions)

acid

• producing H+

• increase H+

• decreases pH

base

• accepts H+

• decrease H+

• basic pH

pH scale

acidic (+7), neutral (0), basic (-7)

how organisms can use buffers to maintain homeostasis

• prevents pH changes

• absorbs/releases H+ to maintain a normal pH range

properties of carbon that make this element the chemical basis of all life

• chemical basis of all life

• atomic structure allows it to form stable, diverse, strong covalent bonds w/ up to 4 other atoms

oxygen

• hydroxyl

• carbonyl

• carbonyl

nitrogen and sulfur

• amino

• sulfhydryl

hydrocarbon and phosphorus

• alkenes + alkene

• phosphate

dehydration synthesis

hydrolysis

carbohydrates

carbon, hydrogen, oxygen (1:2:1)

monosaccharides

• monomer

• simple sugar

• ex: glucose

disaccharides

• polymers

• sucrose

polysaccharides

• glycosidic bonds

• starch, glycogen, cellulose

carb function

• rapid, short term cellular energy

• structural support

• supports cells and organisms (cellulose, chitin)

• story energy (starch, glycogen)

lipids (hydrophobic)

• carbon, hydrogen, oxygen

• long nonpolar hydrocarbon chains

triglycerides

• fats and oils

• 1 glycerol molecule + 3 fatty acids

phospholipids

• steroids, waxes, glycolipids

• glycerol + 2 fatty acids + phosphate group

steroids

• 4 linked carbon rings

structure of a triglyceride

• Saturated: Are those in which all the carbons in the hydrocarbon chain form single bonds.

• Linear

• Mono Unsaturated: Contain one C=C double bond.

• Kink

• Polyunsaturated: 2 or more C=C double bonds.

why some fats are solid at room temperature and others are liquid

• saturated (solid): straight structure, tightly packed, strong attraction, no C=C double bond in hydrocarbon tail

• unsaturated (liquid): bent structure, loosely packed, weaker attraction, at least one C=C double bond in hydrocarbon tail

why phospholipids form a bilayer when dissolved in water

have hydrophilic polar heads and hydrophobic nonpolar tails

chemical nature of steroids and give an example of their biological importance

• core structure

• hydrophobicity

• functional group

• cell membrane stability

amino acid structure

general functions of proteins

• bonding ability to other molecules

• activate special genes

• recognize specific regions of DNA

• interaction with other proteins in the nucleus

• spatial links between domains

amino acid joined to form a polypeptide

primary structure

• linear sequence of amino acids in a polypeptide chain

• held together by covalent peptide bonds

• dictates how the entire protein will ultimately fold

secondary structure

• localized folding and coiling of the polypeptide chain

• alpha helices (coils) and beta-pleated sheets (folds)

• stabilized by hydrogen bonds along the protein backbone

tertiary structure

• 3D shape of a single polypeptide chain

• formed by interactions among amino acid side chains (r groups)

• creates functional, compact protein structures

quaternary structure

• arrangement of 2 or more separate polypeptide chains

• ex: hemoglobin

• held together by the same non-covalent and covalent interactions found in tertiary structure

determines protein shape and function

amino acids

structure of nucleotide

DNA

• deoxyribonucleotides

• deoxyribose

• form double stranded deoxyribonucleic acid for genetic storage

• adenine, thymine, guanine, cytosine

RNA

• ribonucleotides

• ribose

• form single stranded ribonucleic acid for protein synthesis

• adenine, uracil, guanine, cytosine

purines (base)

• adenine and guanine

• 2 fused carbon nitrogen rings

• in DNA and RNA

pyrimidines (base)

• single carbon nitrogen ring

• cytosine is in both DNA and RNA

• thymine is only in DNA

• uracil replaces thymine in RNA

nucleotides

DNA and RNA

central dogma

DNA → RNA → protein

rna base pair

a + u and c + g

dna base pair

a + t and c + g

biological components

atom, small molecules, proteins, viruses, most bacteria and archaea, most plant and animal cells, frog eggs, ant

3 main parts of cell theory

• all living things are made up of cells

• cells are the basic unit of life

• all cells come from pre-existing cells

light microscopy

• light source

• condenser lens

• specimen

• eyepiece lens

transmission electron microscopy

• electron source

• condenser lens

• projection lens

scanning electron microscopy

• electron source

• condenser lens

• scanning coil

• detector

• 3D specimen

cellular components found in all living things

• plasma membrane

• cytoplasm

• DNA

• ribosomes

ratio of surface area to volume limits cells size

a cells volume increases much faster than its surface area as it grows

domain bacteria

• prokaryotic

• absent nucleus

• fatty acids

domain archaea

• prokaryotic

• absent nucleus

• nonfatty acid lipids

domain eukarya

• eukaryotic

• nucleus

• membrane, bounded organelles

• fatty acids

prokaryotic cells

• archaea and bacteria

• no membrane bounded organelles

• nucleoid (center of cell

• generally smaller

• unicellular

eukaryotic cells

• eukarya

• has membrane bounded organelles

• nucleus

• generally larger

• often multicellular but can be unicellular

plant cells

• has a cell wall and cell membrane

• fixed, rigid, rectangular

• has chloroplasts to make food from sunlight

• contains one large central vacuole

• stores extra energy as starch

animal cells

• only has cell membrane

• irregular, flexible, round

• no chloroplast, must absorb nutrients

• few small, scattered vacuoles

• stores extra energy as glycogen

function of membrane

acts as protective barrier that separates the inside of a cell wall from its outside environment while controlling what goes in and out

plasma membrane is a semi-permeable barrier

internal structure is made of a phospholipid bilayer that acts as a selective barrier

structure of a membrane

• phospholipid bilayer

• proteins

• cholesterol

• carbohydrates

• primary function

phospholipid bilayer (membrane)m

• double layer of lipids (base)

• each lipid has a water-loving head and two water-fearing tails. The tails face inward, and the heads face outward.

proteins (membrane)

float inside or span across the lipid layer to move nutrients and send signals

cholesterol (membrane)

tucked inside the layer to keep the membrane stable and flexible

carbohydrates (membrane)

sugars attach to the outside to help cells identify each other

primary function (membrane)

selective gate letting safe materials in while keeping harmful things out

mitochondria

• energy producing

• powerhouse of the cell

• double membrane structures convert nutrients into usable energy thru cellular respiration

• found in plant and animal cells

chloroplasts

• energy producing

• found in plants and algae

• where plants synthesize their food

nucleus

• processing and transport organelles

• largest double membrane organelle

• houses the cells DNA

• coordinates activities like growth and reproduction

endoplasmic reticulum

• processing and transport

• folded membrane network connected to the nucleus

golgi apparatus

• processing and transport

• stack of flattened sacs that modify, sorts, and packages proteins and lipids from the ER for shipment

lysosomes

• breakdown and storage

• recycling and garbage removal centers of the animal cell

ribosomes

• translate mRNA to make protein

• can be free or bounded

eukaryotic endomembrane system

used to modify and move materials within the cell

rough ER

studded with ribosomes to make proteins

smooth ER

makes lipids and handles detoxification

if missing mitochondria (powerhouse)

cell runs out of energy and stops working and dies

if missing lysosome (cleanup crew)

waste builds up inside the cell, causing damage

if missing ribosomes (builders)

cell cannot repair itself or run chemical reactions