Study for the big test with Assessment Statements.
Study for the big test with Assessment Statements.
I hear that this website is not sanctioned in IB Biology anymore. Good that's how it should be. If you're lucky enough to have found this resource, keep it on the downlow. Also, the notes from first and second tri are all here, you have to use the ARCHIVES on the side to find them. The longer ago the ARCHIVE is dated, the longer ago the notes are from. Hence notes from september/october will be the earliest ones in the ARCHIVES. Use the ARCHIVES. Anyone interested in completing this project? email me at firstname.lastname@example.org
Always remember- WERE YOU THERE?
1.1.5 Outline the advantages of using a electron microscope
-.2 nm resolution
1.1.7. Compare relative sizes of :
Molecules (1 nm)
Membranes (10 nm)
(viruses 100 nm)
(bacteria 1 micrometer)
(organelles 10 micrometer)
cells (100 micrometers)
1.1.9 Explain the importance of the surface area to volume ratio
Surface area is important for the cell to maintain water and nutrients. Because these things pass through the membrane, which is the surface area, it needs to have a large surface area to volume ratio. However, when the cell increases in size, the volume increases much faster then the surface area. For example, a cube that is 1x1x1 has a surface area to volume ratio of 6:1. But make the cube 2x2x2 the ratio is 24:8 or 3:1. If you change to 3x3x3, its 54:27, or 2:1. As you can see, the volume increases at a larger rate then surface area. That means to stay happy, the cell must keep that ratio in favor of surface area and split after increasing t a size that makes it hard to keep nutrients coming in and out.
1.3.1 Draw a diagram to show the structure of a eukaryotic cell with ribosomes, rough endoplasmic reticulum, lysosome, golgi apparatus, mitochondria and nucleus
1.3.2 State one function of each of the following organelles:
Ribosomes: Site where the Amino Acids are assembled into polypeptides
Rough Endoplasmic Reticulum: Processing, Transport, and temporary storage of protiens
Lysosome: Destorys old or damaged organelles and foreign particles
Golgo Apparatus: Protiens and Lipids undergo final modification then are sorted out and packaged for specific desitinations
Mitochondria: Uses carbon compounds (glucose) and oxygen to generate energy (ATP) that can be used by the cell as an energy source
Nucleus: Carries out the functions of control and cell reproduction
1.3.4 State three differences between plant and animal cells
Plant cells have rigid cell walls
Plant cells contain vacuoles full of water
Plant cells have chloroplasts.
1.4.4 Define diffusion and osmosis
osmosis- the passive movement of water molecules across a partially permeable membrane from high concentration to low concentration.
Diffusion: the tendency of molecules to move from high concentrations to low concentration
1.4.6 Explain the role of protein pumps and ATP in active transport across membranes
Protein pumps act to actively transport sodium, potassium and other materials across the cell membrane to bring in nutrients or dispose of waste
ATP: stores energy in its bonds to fuel cell work, especially transportation in the cell membrane
1.5.3 Describe the events that occur in the four phases of mitosis
prophase: Chromatin condenses into sister chromosomes held by a centromere. Tubules and stuff all made.
metaphase: sister chromosomes line up in the center on metaphase plate attached to centrosome poles
anaphase: the chromosomes are split and pulled apart
telophase: chromatin reforms, nuclear envelope is reformed, clean up occurs.
2.1.2. State that a variety of other elements are needed by living organisms including nitrogen, calcium, phosphorus, iron and sodium
Other elements are needed by living organisms
2.1.3 What do above elements do?
Nitrogen: part of DNA
Calcium: plants use it for transmitting food
Sodium: Na-K pump
2.3.3 Explain the effects of temperature, pH and substrate concentration of enzyme activity.
Temperature, pH and substrate concentration all effect enzyme activity by maximizing conditions for reactions or denaturating enzymes (heat and pH only)
2.3.4 Define denaturation:
A structural change in a protein that results in a loss of its biological properties. Heat and pH.
2.4.1 Outline DNA nucleotide structure in terms of sugar, base and phosphate
A DNA nucleotide is a phosphate-sugar-base
2.6.1 Compare the structure of RNA and DNA (sugars, bases, and number of strands)
Compare the structure of RNA and DNA (sugars, bases, and number of strands) RNA: Ribose, Base = Uracil, and single strand DNA: Deoxyribose, base = Thymine, two strand
2.6.2 Outline DNA transcription in terms of the formation of an RNA strand complementary to the DNA strand by RNA polymerase.
Helicase unwinds DNA, RNA polymerases I, II and III come in and do there work. The exons and introns are cut by spliceosome
Chlorophyll in the main photosynthetic pigment.
2.8.8 Outline the effects of temperature, light intensity and carbon dioxide concentration on the rate of photosynthesis
they do shit
3.1.4 Define gene, allele and genome.
Gene- a heritable factor that controls a specific characteristic
Allele- one specific form of a gene, differing from other alleles.
Genome- the whole of the genetic information of an organism
3.1.6 Explain the consequences of a base substitution mutation in relation to the process of transcription and translation, using the example of sickle cell anemia
GAG has mutated to GTG causing glutamic acid to be replaced by valine and hence sickle cell anemia. Good in areas of high malaria to be heterozygous, but fatal in homozygous.
3.2.6 State Mendel's Law of segregation
Alleles distribute independently of one another
3.3.5 Describe ABO blood groups as an example of co dominance and multiple alleles.
O is recessive A and B are codominant.
3.3.8 Define sex linkage
A trait linked to gender through chromosomes
Gel electrophoresis separates fragmented DNA by charge and size
3.4.5 Define genetic screening
Genetic screening involves testing an individuals genome for genetic predispositions to certain conditions
3.4.6 Discuss three advantages and/or disadvantages of genetic screening Can correct genetic problems in fetus
Can help prepare for genetic disorders
Can correct genetic problems in fetus
Can result in genetic discrimination
ecology: the study of the relationship between organisms and their environment
ecosystem: a community and its abiotic environment
population: a group of the same species in the same area
community: a group of populations in a given area
species: a group of organisms which can interbreed and produce fertile offspring
habitat: normal living environment for a species.
Detritivore: decomposes organic matter
Saprotroph: decomposes inorganic matter.
4.1.5 Describe what is meant by a web web
A food web shows all the interactions of species in a community
4.2.3 explain sinusoidal growth
a population once established will grow exponentially until the environment cannot sustain growth any further and then the population plateaus as K capacity is reached.
4.2.4 Define carrying capacity
Carrying capacity is the maximum amount of individuals a habitat can sustain.
4.2.7 Describe catch-recatch counting technique 7.1.6 Explain the relationship between a mitochondria’s shape and its function
Catch, mark, release, catch, count, mark, release.
4.3.1 Define evolution
Scientists trying to kill god with lies.
A series of slow changes changing one species to another.
4.3.8 Two examples of evolution in response to environmental change
Antibiotic resistance. Moth in
4.4.5 List hiercy
Kingdom, Phylum, Class, Order, Family, Genus, Species
6.1.3 Describe the structure of DNA including parallel and anti-parallel strands.
DNA has two strands which go in the 3-5 direction. A and T are paired as are G and C, they are purines and pymridines. AG are purines, TC are pymridines.
Reverse transcriptase catalyses the production of DNA from RNA. (AIDS as an example)
6.4.2 Outline the structure of ribosomes, including protein and RNA composition, large and small subunits, two tRNA binding sites and mRNA binding sites.
6.4.5 Explain the process of translation including ribosomes, polusomes, start codons, and stop codons
A small riboseribosomal subunit brings a start codon to the mRNA which indicates the mRNA to build protein. Then it is joined by a large ribosomal subunit and a tRNA. Then Methionine is added to the start codon and the process goes down stream with AA being introduced at the A side, put togther on the P site, and leaving on the E site. Later the tRNA reaches a stop codon and a protein Explain the process of translation including ribosomes, polysomes, start codons and stop codons.
6.5.1 Explain the four levels of protein structure, indicationg each level's significance:
Primary Structure: amino acid sequence
Secondary Sequence: highly patterned sub-structures
Tertiary structure: the overall shape of a single protein molecule
Quaternary structure: the shape or structure of the whole chain of protein molecules
6.6.2 Describe the induced fit model
This is a modification to the lock and key model. It states that the active site of an enzyme is not precise, but roughly the right shape. The enzyme moves so the substrate fits into it, which causes but it stresses the substrate and the enzyme moves to fit the enzyme. It is like how a glove changes its shape when you pull it over your hand. (the glove is the enzyme). This tendency causes the enzyme to stress the bonds of the substrate. It can also change the pH or covalently bond with the substrate, which causes the activation energy to lower. The stress on the enzyme can help break bonds in the substrate.
6.6.4 Explain the differences between competitive and non competitive inhibitions with reference to one example of each
Competitive inhibitors compete directly with substrates at the active sites. They block the entrances to the active sites. The neurotoxin Diisopropylfluorophosphate binds to the active site of cholinesterase, which produces a neurotransmitter responsible for movement.
Noncompetitive inhibitors change the shape of the active site by binding to the enzyme somewhere else. This contorts the entire shape of the enzyme rendering it unable to work. Cyanide binds to oxidase, changing its shape so it can’t perform respiration
The mitochondria’s cristae are folded to allow maximum surface area to create a proton gradient. The spaces between the cristae holds protons.
7.1.6 Explain the relationship between a mitochondria’s shape and its function
Thylakoid have large surface area to increase light absorption. The small spaces inside the thylakoid holds protons.
8.3.1 State the difference between autosomes and sex-chromosomes.
Autsomes are identical pairs of chromosomes in a species despite gender.
Chromosomes that determine sexual characteristics are sex-chromosomes.
8.4.1 Define polygenetic inheritance
Multiple genes code for one trait
13.2.2 Describe the process of mineral uptake into roots by active transports
13.2.3 Explain the process of root uptake by root epidermis cells and its movement by the symplastic and apolplastic routes across the root to the xylem.
13.2.7 State that guard cells close and open stomata
Guard cells close and open stomata
13.3.1 Draw the structure of a dicot
13.3.3 Distinguish between pollination, fertilization and seed dispersal.
d.1.2 Outline the experiments of Miller and Urey in the origin of organic compounds
The replicated primordial soup conditions and organic compounds were formed, including amino acids.
d.2.3 Explain the Darwin-Wallace theory of evolution by natural selection
The fittest survive to pass on their traits.
d.3.1 Describe the eveidence for evolution as shown by the geographical distribution of living organisms, including the distribution of placental, marsupial and monotreme animals.
d.3.10 Explain the evidence of evolution provided by homologous anatomical structures, including vertebrate embryos and the pentadactyl limbs.
Homologous structures, for example seal flippers and human hands. Vertebrate embryos essentially show reverse evolution.
d.3.11 Outline two modern examples of observed evolution. One example must be the changes to the size and shape of the beaks of Galapagos finches.
d.4.4 Outline the trends illustrated by the fossils of Australopithecus including A. afarensis, A. africanus and A. robusto and homo including H. habulis, H erectus, H neadanderthalensis and H sapiens.
d.5.4 adaptations may occur as the result of an allele frequency increasing in a populations gene pool over a number of generations.
d.5.6 State that a species is a potentially interbreeding population having a common gene pool.
d.5.9 Discuss ideas on the pace of evolution including gradualism and punctuated equilibrium.
Gradualism is the slow change from one form to another. Punctuated equilibrium, however, implies long periods with no change and short periods of rapid evolution. (natural diasters change conditions)
d.6.2 Explain how the Hardy-Weinberg equation (p2+ 2pq + q2 is derived)
P represents the probability of a dominate (hetro or homo) individual and q represents the probability of a recessive individual (homo), so 1 individual is represented by P+Q, or the sum of the probability that is dominate and and the probability it is recessive. This is of course equal to 1. When one theoretical individual reproduces with another individual, their probabilities are multiplied together. (P+Q) * (P+Q) yielding P^2 + 2pq + q^2
d.6.5 State the Hardy-Weinberg principle and the conditions under which it applies
Random mating, large population. No mutation, nor mortality nor migration. Under these conditions population remains at equilibrium originally established
Chapter 15 Retroviruses and Chapter 14 Gene Regulation
I Retroviruses and Reverse Transcriptase
--1. Viruses that use the enzyme reverse transcriptase to make sequences of single and double stranded DNA sequences from RNA.
--2. Example (need to know): AIDS (Acquired Immune Deficiency Syndrome):
---a. The genome of HIV is made of RNA, not DNA
---b. Reverse transcriptase has a high error rate (up to about 1 in 2,000 bases when transcribing RNA into DNA, which allows retroviruses to mutate rapidly)
---c. When HIV enters lymphocyte cells, it makes DNA from RNA using reverse transcriptase
---d. this DNA becomes inserted into the lymphocyte’s chromosome
---e. now when the lymphocyte replicates, the viral DNA is replicated as well.
---f. when the DNA is transcribed it produces viral mRNA, some of which will eventually be translated into viral proteins
---g. drugs can fool reverse transcriptase into incorporating it into the growing DNA strand instead of the HIV which then halts further DNA synthesis
---h. the reverse transcriptase of the virus HIV prefers AZT 3phosphate to the normal nucleotide, deoxribose nucleoside triphosphate that has no 3 hydroxyl to which to add the next nucleotide therefre chain elongation comes to a halt and the virus cannot replicate
-B. Use of Reverse Transcriptase in Molecular Biology
--1. Reverse transcriptase can be used to make DNA from mature mRNA
---a. example: the mature mRNA that codes for human insulin can be made into DNA using reverse transcriptase.
---b. This is then spliced into host DNA such as E. Coli (most E. Coli is good) which reproduce, making more of the DNA that codes for insulin, making E. Coli into our slaves!
II. Gene Regulation
--1. In all species, most of the genes, most of the time are shut down and only a very small portion are transcribing/translation in order to make proteins
--2. There must be a coordination between when a gene is transcribed and cellular metabolism
--3. Two basic “ports” of a gene
---a. Coding region- codes for mRNA and protein
---b. Regulator region- controls transcription of the coding region
-B. Gene Regulation in prokaryotes
--1. Operon: several protein coding regions on a gene under the control of a regulatory region consists of a prometer and an operator.
--2. Example: The Lac Operon Complex in E. Coli
---a. E. Coli can use lactose when glucose is not available
---b. The enzymes necessary to do this are normally no produced by E. Coli.
---c. However, they can be produced when lactose is present
----i. therefore lactoscis is an inducer molecule
-C. Gene regulation in Eukaryotes
--1. Much less is known than in prokaryotes
--2. Control systems utilizing regulatory proteins to bind to DNA much like operon represors, also exists in eukaryotes
--3. Some genes are activated by:
---b steroid binding
---c. uncoiling of nucleosomes
III. Chapter 17 DNA changes
-A. DNA is stable
--1. bases are protected
--2. Tigh wrapping around histone (eukaryotes) and coiling don’t allow for direct access to DNA
--3. Complimentary base pairings to fix any accidental changes
-B. Frequency of Mutations
--1. In humans and other mammals, uncorrected Errors in mutations occur at the rate of about 1 in 50 million nucleotides added to the chains. With 6 billion base pairs in a human cell, that means each new cell contains about 120 new mutations.
--2. However, not that big of deal because of synomous codons and repetitive DDNA that doesn’t code for proteins.
--3. For eukaryotes, this often happens during S phase of interphase where all DNA is replicated into 2 copies called chromatids.
-C. DNA Damage:
--1. Mutagens are agents that cause mutations- a failure to repair DNA
--2. Radiation forms of energy (gamma rays, x-rays, UV) that penetration the cells and damage DNA
--3. Chemicals damage DNA through chemical reactions
-D. 3 levels of mutational change
--1. Point or Single Base Mutations
---a. Involves changes in one or only a few nucleotides in DNA
---b. 3 types:
----i. Base substitution: Substitution of a single base pair. 3 outcomes:
-----Silent mutation has no effect on structure of resulting protein because of degenerative
-----Neutral Mutations- changes in amino acide in protein but has no effect
----- Drastic mutation- has serious effects on structure or proteins. Example: Sickle Cell disease and Tay Sacs disease.
----ii. Chain Termination mutations- either new mutated codon produced is stop codon or stop codon is made into a not stop codon
---iii. Frameshift mutation- results from the deletion and additions of bases into a nucleotide sequence. These cause shifts in the reading of codons during transcription and results in an abnormal polypeptide
--2. Chromosomal Mutation
---a. involves major changes in chromosomal structure rather then simple DNA sequence changes
---b. There is a complete breaking, misalignment and rejoing of the double helix in one or more chromosomes.
---c. Three types:
----i. delections- entire sections left out
----ii. Inversion- a middle fragment of DNA may flip over and rejoins
----iii. Translocation- 2 nonhomologous chromosomes break, swap segments and fuse together
---a. certain segments of DNA frequently “jumps” (sometimes called jumping genes) to new locations in the same DNA molecule or a different one these are called transposable elements
---b. Not caused by mutagens but are considered mutagens themselves because they cause the mutations
---c. First found in corn and then in E. Coli
---d. discovered by Barbara Clinton (nobel Prize)
I. Photosynthesis Overview:
I. Pages 126- 132
Need to learn about enzymes? For some basic information go here.
I. Enzyme Packet
Chapter 3: The Molecules of Life
I. Dehydration reaction (In IB terms, Condensation)
Note to readers
This site is intended for CHS IB Biology students in Mr. Jansen's class. It will have notes verbatim, an analysis of those notes, previews of quizzes and tests, post-views of quizzes and tests, IB objectives, and other useful items. Special thanks to Ben Hollingsworth for providing an electronic copy of his notes for chapters 1-4. Please comment on the post with questions, answers, tips and analysis. Email me if you have specific queries. The first real entry will be Chapter One notes.
Welcome fellow IBer's. If you are here to study, you have come to the right place. This is an open forum of notes, IB objectives and fun! Please make use of this site. Over time, entries from the begining will find there way into the "archives." This will be a valuable tool for when it is time for finals and tests. Feel free to make appropiate comments. Email me with suggestions for improvment as well. Keep in mind these notes should be paired with the book and in class labs.