FINAL EXAM STUDY GUIDE KEY
GENETICS
Mendel: “father” of genetics, worked with pea plants, determined two laws for heredity, studied
heredity traits
Mendel’s 2 laws of inheritance
- The Law of Segregation: during the formation of gametes, alleles responsible for a trait
separate; this allows for recombination during fertilization.
- The Law of Independent Assortment: alleles responsible for different traits are distributed to
gametes (and thus the offspring) independently of each other.
F1/F2 generation:
F1: The first filial generation, which is comprised of offspring(s) resulting from a cross between
strains of distinct genotypes
F2: The second filial generation, which is comprised of offspring(s) resulting from a cross
between the F1 generation
Punnett square: diagram that is used to predict an outcome of a particular cross or breeding
experiment
Heredity: passing of traits to offspring from its parents or ancestor
Crossing-over: accounts for genetic variation due to the swapping of genetic material during
prophase I of meiosis
Homozygous, pure bred: refers to having identical alleles for a single trait (ex: TT, tt)
Heterozygous, hybrid: refers to having different alleles for a single trait (ex: Tt)
Dominant/recessive: dominant traits are shown more often in phenotype and have the ability to
mask the recessive traits
Genotype, phenotype, allele: genotype is the genetic makeup of a gene and phenotype is the
physical representation of the trait. An allele is the letter representation of the trait
Haploid/diploid: haploid is half the amount of chromosomes (ex: an egg/sperm cell) and diploid
means two copies of each chromosome
Co dominance: When both alleles are dominant and are BOTH EXPRESSED to make a third
phenotype
Incomplete Dominance: When both alleles are dominant and are BLENDED to make a third
phenotype
Sex-Linked (give an example): traits that occur on sex chromosomes (ex: colorblindness,
hemophilia)
Multiple allele traits: traits that use more than 2 alleles (ex: blood typing I A, IB, i)
Sex chromosomes: Male: XY/Female: XX
Karyotype (know how to read and analyze): can determine sex of the individual and whether
there is a nondisjunction chromosomal disorder (below is a male with no chromosomal disorder)
Be able to analyze blood types as co-dominant and multiple alleles
Be able to set up and complete a dihybrid Punnett square and analyze probability ratios
for genotype and phenotype.
Homologous/Non-homologous chromosomes: chromosome pairs of approximately the same
length, centromere position, and gene locations. Non-homologous are not the same
Mutations of gametes:
Deletion, inversion, translocation, non-disjunction
Are mutations good or bad? Or neutral? Can be all of the above
How is Down’s syndrome caused? Non-disjunction mutation during meiosis where there is an
extra chromosome number 21
Pedigree chart (know how to read and analyze):
DNA, RNA, & PROTEIN SYNTHESIS
Know differences and similarities between DNA and RNA
Monomer of nucleic acid: nucleotide
Parts of a nucleotide: sugar, phosphate group, nitrogenous base
Chargaff’s Rule: complimentary base pairing where A=T, G=C
Codon: three letter sequence that codes for an amino acid
mRNA: messenger RNA, recipe for protein
rRNA: ribosomal RNA, make up ribosomes
tRNA: transfer RNA, brings amino acids to the ribosome to assemble protein
Know how to determine complimentary strands of RNA from DNA sequence Ex: ATTGCGATCGAT
A=T, G=C Ex: TAACGCTAGCTA
Transcription: process of DNA being coded into RNA
Translation: process of RNA being coded into a protein
HISTORY OF LIFE
Spontaneous generation: obsolete body of thought on the ordinary formation of living organisms
without descent from similar organisms
Biogenesis: process that living things come into existence from other living things
Redi’s experiments:
Pasteur’s experiments:
Spallanzani’s experiments:
Miller and Urey’s experiments:
Oparin’s beliefs: hypothesized that the formation of amino acids and proteins from non-living
chemicals
Age of Earth: approximately 4.6 billion years old
Half-Life: time required for a quantity of radioactive isotopes to fall to half its value as measured
at the beginning of the time period to determine age of something
Isotope: element with more or less neutrons
Be able to calculate half-life: If the half-life of (carbon 14-12) is 5,000 years old, how many halflives did carbon go through to be 15,000 years old. How much parent material is left over, how
much daughter material is left over?
3 half-lifes, there is 1/8 of C-14 left
Evolution of DNA/RNA-which came first? RNA came first and then DNA
Examples of Fossils: bones, remains on rocks, impressions
First living organisms that exist today: prokaryotic and heterotrophic
EVOLUTION
Darwin: “father” of evolution, established that all species of life have descended over time from
common ancestors, and proposed the scientific theory that this branching pattern of evolution
resulted from a process that he called natural selection, in which the struggle for existence has a
similar effect to the artificial selection involved in selective breeding
Were his ideas accepted at first? No since many scientists had only religious beliefs
Darwin’s trip on the Beagle:
Idea of a common ancestor: theory that organisms evolved from one common organism and later
speciation lead them to differ
Adaptation: a change in an organism to better suit the environment
Natural Selection and the importance of genetic variation (peppered moth color): nature
choosing which organisms are best adapted for their environment to mate with, idea of survival
of the fittest where the organisms that survive are best adapted for their surroundings and will
be able to reach sexual maturity and reproduce
Explain the peppered moth scenario in England during industrial revolution. What is industrial
melanism? Originally, the vast majority of peppered moths had light coloration, which
camouflaged them against the light-colored trees and lichens which they rested upon. However,
because of widespread pollution during the Industrial Revolution in England, many of the lichens
died out, and the trees that peppered moths rested on became blackened by soot, causing most of
the light-colored moths to die off from predation. At the same time, the dark-colored moths
flourished because of their ability to hide on the darkened trees.
Homologous structures (explain) and how they can be proof of a common ancestor and show
similar DNA base patterns in different species that are related: may not necessarily perform the
same function but they share a common ancestral origin
Analogous structures: s of different species having similar or corresponding function but not
from the same evolutionary origin
Vestigial structures: remnants of structures found in the ancestral species (ex: appendix,
tailbone)
Gradualism: most evolution is marked by long periods of evolutionary stability
Divergent Evolution: accumulation of differences between groups which can lead to the
formation of new species
Convergent Evolution: process whereby organisms not closely related independently evolve
similar traits as a result of having to adapt to similar environments
Co evolution: when 2 or more organisms evolve together
Speciation and how it can occur by geographic isolation (CA Salmander): speciation that occurs
when populations of the same species become isolated from each other to an extent that changes
their genetic makeup
Lamarck-acquired characteristic theory: idea that an organism can pass on characteristics that it
acquired during its lifetime to its offspring
Hardy-Weinberg Equilibrium populations:
5 factors that exist in an evolving population (understand what they mean)
5 factors that do not exist in an evolving population, but exist hypothetically in a H-W equilibrium
population
If 36% of a dog population are recessive for white fur, what is the genotypic percentages of the
rest of the dominant genotypes for black fur AA and Aa? Show your work.
q2= 36%, q= 6%, p= 4%, p2= 16%, 2pq= 48%
AA = p2 = 16% and Aa = 2pq = 48%
If 16% of a yellow bird population is recessive for yellow feathers, find the percentages of the 2
other genotypes for the dominant red feathers RR and Rr. Show your work.
q2= 16%, q= 4%, p= 6%, p2= 36%, 2pq= 48%
AA = p2 = 36% and Aa = 2pq = 48%
BIOTECHNOLOGY (GENE TECHNOLOGY)
Genome: all of an organisms genetic information
Gene therapy: use of DNA as a pharmaceutical agent to treat disease
Operon (lac operon example – when is it on/off): operon is on when lactose is present and off
when lactose is absent ( lactase enzyme is only made when needed to conserve energy)
Operator: on/off switch where repressor binds
Repressor: protein that binds to operator to turn operon off
RNA Polymerase: enzyme that codes DNA to RNA
Genetically modified foods/animals:
-
How do we do this? Why is this important? Give examples of kinds of genetic
engineering
-
Specific changes introduced into their DNA by genetic engineering techniques. We can
create recombinant DNA by introducing a segment of DNA from another species into an
organism. This is important because we can alter nutrition of foods, sizes of crop,
resistance to insects and herbicides as well as create organisms that can make human
genes. Genetically modified tomatoes with arctic flounder DNA to withstand cold
temperatures and bacteria cells creating insulin
PCR: process of making copies of DNA segments
Gel Electrophoresis: gene technology where DNA segments are arranged and organized on a gel
by their size and charge
Cloning: process of making identical cells
Restriction Enzymes: proteins that cut specific areas on a DNA segment
“Sticky ends”: over hang left from restriction enzymes cutting DNA
Recombinant DNA: having DNA from 2 or more organisms in one cell
Plasmid: circular chromosome found in bacterial cells that is not necessary for bacteria to live
Introns: non-coded regions of DNA
Exons: coded regions of DNA that exit the nucleus and code for protein
Human Genome Project: project to map out all the chromosomes in our genome and explain what
each one codes for
ECOLOGY
Ecology: study of interactions among organisms and their environment
Population: sum of all the organisms of the same group or species, who live in the same
geographical area, and have the capability of interbreeding
Ecosystem: community of living organism in conjunction with the nonliving components of their
environment
Habitat: ecological or environmental area that is inhabited by a particular species of animal,
plant, or other type of organism
Niche: term describing the way of life of a species
Food chains/food webs: linear consequence of links in a food web starting from a species that
eats no other species in the web and ends at a species that is eaten by decomposers
Producers, primary consumers, secondary consumers, tertiary consumers: producers create their
own food and their source of energy is from the sun, primary consumers eat the producers,
secondary consumers eat primary consumers, tertiary consumers eat secondary consumers
Relationships (parasitism, mutualism, commensalism):
Herbivore: organism that eats plants
Carnivore: organism that eats meat
Omnivore: organism that eats plants and meat
Detrivore: organism that eats remains of animals
Decomposer: organism that eats remains of animals, is a tertiary or quaternary consumer and
provides energy back into the environment
Understand trophic levels in a pyramid and how energy is transferred up each level and lost.
Abiotic/Biotic factors: Abiotic are non-living factor, biotic are living factors that affect the
organism
Make a food chain and label all types of producers/consumers
Lady bug, grass, hawk, fox, bird
Grass  lady bug  bird  fox  hawk
Producer  primary consumer  secondary consumer  tertiary consumer  quaternary
consumer