Biology Exam 2
What is a genetic code?
- describes which amino acid is specified by each codon
Anticodons (What are they? On what molecule are they found?)
-3 bases that complement to that of the corresponding codon -found on tRNA
Codons (What are they? On what molecule are they found?)
-3 bases that represent one amino acid -found on mRNA
What are the base pairing rules in DNA?
-A&T -G&C
Describe endosymbiosis theory. Know evidence for this theory.
-Chloroplast came from cyanobacteria (evidence: presence of chloroplast in plants and algae) -mitochondria came from aerobic bacteria (evidence: presence of mitochondria in plants and animals)
What type of bond is found between nitrogenous bases?
-Hydrogen bonds (the bond that holds the opposite strands together)
Compare and contrast rough ER and smooth ER
-Rough ER: modifies proteins - Smooth ER: lipid synthesis, detoxification
What is a promoter?
-a region of DNA where RNA polymerase binds to initiate transcription
Which nitrogenous bases are found in the nucleotides found in RNA?
-adenine, guanine, cytosine and uracil
What molecules are involved in translation?
-amino acids, rRNA, mRNA, and tRNA
What type of bond is between nucleotides of the same strand?
-phosphodiester bond
What are the different functions of proteins?
-structural: hair, fingernails, feathers, horns, cartilage, tendons -protective: help fight microorganisms -regulatory: control cell activity -contractile: allows muscles to contract, heart to pump, sperm to swim -transport: carry oxygen
During Translation, which molecule acts as the translator? Explain how.
-tRNA acts as the translator between mRNA and protein by bringing the specific amino acid coded for by the mRNA codon
___ molecules diffuse readily across the membrane. a. Water b. Hydrogen ions c. Hydrophillic d. Carbon dioxide
Carbon dioxide
What are features common to all cells?
Cell membrane, DNA, ribosomes and cytoplasm
Which macromolecule contains an organism's genetic information? 1.DNA 2.polysaccharide 3.monosaccharide 4.Phospholipid 5.fatty acid
DNA
Roles of DNA and RNA
DNA is storage of information that cannot leave the nucleus; RNA converts DNA into proteins
What is a terminator?
DNA sequence that signals the end of transcription
Lipid soluble molecules such as alcohol cannot diffuse through the plasma membrane. 1. True 2. False
False
The plasma membrane (cell membrane) does not have any cholesterol. 1. True 2. False
False
Which of the following foods is not a significant source of complex carbohydrates? 1.all of the listed 2.pasta 3.oatmeal 4.rice 5.Fresh fruit
Fresh fruit
processes products for delivery throughout the body
Golgi apparatus
Which 4 bases are found in DNA nucleotides?
Guanine, adenine, cystonine, thymine
Unlike saturated fatty acids, unsaturated fatty acids ___ 1.are solid at room temperature 2.Have one or more double bonds in their hydrocarbon chain 3.pack more tightly because they have straight chains 4.None of the above
Have one or more double bonds in their hydrocarbon chain
___ helps to transport hydrophillic substances to the interior of the cell a. Cholesterol b. Integral membrane protein c. Peripheral membrane protein d. all of the above
Integral membrane protein
harvests energy to be used for cellular function
Mitochondria
Compare and contrast the prokaryotic and eukaryotic cell structure.
Prokaryotic -small -no nucleus -no organelles -basic structure includes: plasma membrane, cytoplasm, ribosomes, DNA, cell wall, pili, and flagellum Eukaryotic -large -has a nucleus & organelles
Which part of the cell membrane helps in cell-cell signaling? a.Carbohydrates b.Unsaturated fatty acids c.Proteins d.Cholesterol
Proteins
In section 9 (ion channel section) of the second website the S. lividans channel protein is shown. This protein represents a protein in the ____ structural level. a.Primary b.Secondary c.Tertiary d.Quarternary
Quarternary
At the end of transcription what is formed?
RNA molecule
What enzyme is involved in transcription?
RNA polymerase
Name two important nucleic acids found in all cells
RNA, DNA
In general, which of the follwoing will diffuse across a lipid bilayer most rapidly. a. Small hydrophillic molecule b. Small hydrophobic molecule c. Large hydrophillic molecule d. Large hydrophobic molecule
Small hydrophobic molecule
synthesizes lipids, detoxifies molecules
Smooth ER
Which of the following about starch is incorrect? 1.Starch is a polysaccharide 2.All the statements about starch are incorrect 3.Starch is the primary form of energy storage in plants 4.Starch consists of a hundred or more glucose molecules joined together in a line 5.Starch tastes sweet because it is made from glucose
Starch tastes sweet because it is made from glucose
THe more the amount of lipids in a molecule the easier it is for that molecule to pass through a plasma membrane (cell membrane). 1. True 2. False
True
first to describe the structure of DNA.
Watson and Crick (1953)
Who got the Nobel Prize for discovering the DNA structure?
Watson, Crick, and Wilkins
What are phospholipids?
a lipid containing a phosphate group in its molecule
solute molecules use the transport protein as a pump with ATP to go from low to high concentration
active transport
A denatured protein has lost its ____ 1.shape 2.hydrogen bonds 3.function 4.all of the above
all of the above
A protein is a polymer of ____ 1.amino acids 2.polypeptides 3.Oligosaccharides 4.Lipids 5.nucleic acids
amino acids
What simple molecules are the building blocks of proteins?
amino acids
At the end of translation what is formed?
an amino acid
___ allows water into and out of the cell. a. Phospholipids b. Aquaporin c. Transport protein d. Cholesterol
aquaporin
List the two types of prokaryotes
bacteria and archaea
have a structural role as a physical barrier and participate in cell recognition and adhesion, either cell cell signaling or cell pathogen interactions
carbohydrates
What are the different molecules that make up a cell membrane
carbohydrates, lipids, and proteins
What are the macro molecules?
carbohydrates, proteins, lipids, and nucleic acids
Organic molecules consist mainly of _____ 1.carbon 2.carbon and oxygen 3.carbon and hydrogen 4.carbon and nitrogen
carbon and hydrogen
What are the elements common to all macromolecules.
carbon, hydrogen, and oxygen
provides additional protection and support for plant cells
cell wall
the plant cells power plant (site of photosynthesis)
chloroplast
All of the following are proteins except ___ 1.an insulin 2.an antibody 3.an enzyme 4.cholesterol 5.hemoglobin
cholesterol
THe more the amount of lipids in a molecule the easier it is for that molecule to pass through a plasma membrane (cell membrane). a. Glycoproteins b. Trasnsport proteins c. Surface (peripheral proteins) d. Cholesterol
cholesterol
Peptide bonds in proteins _____ 1.connect amino acids to sugar monomers 2.bind phosphate groups to adenine 3.connect amino acids together 4.connect nitrogen base to ribose monomers
connect amino acids together
Where does translation occur?
cytoplasm
Cilia and flagella are part of the
cytoskeleton
physical support, cell division and movement
cytoskeleton
molecules cross the membrane from high to low concentration
diffusion
Sucrose (table sugar) and lactose (the sugar found in milk) are examples of 1.monosaccarides 2.complex carbohydrates 3.simple sugars 4.naturally occurring enzymes 5.disaccharides
disaccharides
Facilitated diffusion ___ requires energy and uses the help of ____ a. Does; transport protein b. Does; cytoplasm c. does not; transport protein d. does not; sodium pumps
does not; transport protein
solute molecules travel through the transport protein, high to low concentration
facilitated diffusion
What are the examples of lipids found in living cells?
fats, sterols, phospholipids, waxes
What happens to a protein when it gets denatured?
gets broken down and the H bonds unfold
Which of the following are all monosaccharides? 1.fructose and cellulose 2.glycogen and glucose 3.starch, cellulose and glycogen 4.glucose and maltose 5.glucose, fructose and galactose
glucose, fructose and galactose
3 examples of monosaccharides
glucose, fructose, galactose
What simple molecules (monomers) are the building blocks of complex carbohydrates?
glucose, fructose, galactose
All of the following are lipids except ____ 1.insulin 2.steroids 3.triglycerides 4.cholesterol 5.fats
insulin
What are macro molecules?
large molecules, simple and composed of carbon, hydrogen and oxygen (organic compounds)
Sterols are classified as _____ 1.lipids 2.sugars 3.proteins 4.nucleotides
lipids
regulatory agents in cell growth and adhesion
lipids
The ___ part of the cell membrane functions as a barrier while the ___ does most of the transport. a.Lipids; Proteins b.Glycogen; protein c.Carbohydrates; Lipids d.Glycoprotein; lipids
lipids; proteins
acts as floating garbage disposals for cell digestion & recycling cellular waste products & consumed materials; breaks down different elements
lysosome
(messenger) carries the genetic code
mRNA
Each cell can perform all basic functions of life including:
metabolism, homeostasis, and reproduction.
What element besides C, H and O is present in amino acids?
nitrogen and sulfur
In addition to those elements DNA contains __________ and _________
nitrogen, phosphorus
Is the cell membrane static (stiff)? 1. yes 2. no
no
What simple molecules are the building blocks of nucleic acids?
nucleotides
Where does transcription occur?
nucleus
What causes denaturation?
pH and temperature
What is the name for the covalent bond that forms between amino acids?
peptide bonds
Structure of a DNA nucleotide
phosphate group, sugar, nitrogen base
Describe the basic structure of a nucleotide
phosphate group, sugar, nitrogenous base
Breakdown of ____ part of cell membrane leads to break up of the cell itself. a.Carbohydrates b.Proteins c.Glycoproteins d.Phospholipid
phospholipid
What are the 4 levels of protein structure?
primary, secondary, tertiary, quaternary
enzymes to speed up chemical reactions, acts as receptors for specific molecules, or transport materials across the cell membrane
proteins
At which level are proteins functional?
quaternary
(ribosomal) along with ribosomes, help make proteins
rRNA
The most common purpose of proteins is to serve as ____ 1.raw material for growth 2.fuel for running the body 3.organic precursor for enzyme construction 4.long term energy storage 5.storage of genetic information
raw material for growth
produces proteins
ribosomes
modifies proteins that will be shipped elsewhere in the organism
rough ER
Differences between saturated and unsaturated fatty acids.
saturated is solid; unsaturated is liquid
Is RNA a single stranded nucleic acid or a double stranded nucleic acid?
single stranded
THe lipid bilayer is not permeable to ____ a. Carbon dioxide b. Lipids c. Oxygen d. Sodium ions
sodium ions
All of the following are carbohydrates except ___ 1.starch 2.spider's silk 3.glycogen 4.cellulose 5.chitin
spider's silk
What are 3 examples of complex carbohydrates (polysaccharides)
starch, cellulose, chitin
2 examples of disaccharides
sucrose, lactose
What type of backbone does a strand of DNA have?
sugar and phosphate
(transfer) carries amino acids to ribosomes
tRNA
What is the function of the cell membrane?
to control what enters and leaves the cell
Stores water and ions
vacuole
multipurpose storage sacs for cells (functions: nutrient storage, waste management, predator deterrence, physical support, sexual reproduction)
vacuoles
What "roles" do lipids play within living things?
warmth, energy
Can RNA leave the nucleus? If so, how does it leave the nucleus?
yes, by transcription