Semester Wrap-Up and Final Exam Review

BSC 2010Fall 2013

Final Exam

• SI Final Exam Review: Tuesday, December 3rd from 10:30 AM - 12:30 PM

• Student Union, 2nd floor, Key West 218ABCD room (minirooms A, B, C, and D will be combined into one room for this purpose).

Final Exam• Final Exams: • Section 2 (10:30 am – 11:20 am): Monday, Dec.

9th from 10:00 am to 12:50 pm• Section 3 (11:30 am – 12:20 pm): Wednesday,

Dec. 4th from 10 am to 12:50 pm– You must attend the final exam for your registered

class – Exam collection will begin 1 hr after exam begins,

no students will be permitted to begin exam after collection begins

• What You Need to Bring:– Pencil, Photo ID, Calculator

Final Exam

• Total Number of Questions: 75 questions + 5 bonus point questions– Old Material: 39 questions– New Material: 36 questions

• Review Document posted on Webcourses• Types of Questions:

1. Multiple Choice2. True/False

Final Exam• Chapters 1 and 2• Main Concepts:• Biology is the study of life– Taxonomy

• Chemistry– Molecular Bonds

• Scientific Method and Hypotheses• Vocabulary:– Valence shell

Hypotheses• H0 = There is no difference

• Example: There will be no difference in the stalking behavior of lions born in zoos and lions born in the wild

• HA = There is a difference

• Example: Lions born in the wild will stalk prey more efficiently than those born in zoos.

Chapter 2

• Molecular Bonds between Atoms• The outermost orbital is called the valence shell. • When the valence electrons of atoms interact

chemical bonds are formed• Several types are important in biological systems:– Covalent- electrons are shared – Ionic- transfer of electrons– Hydrogen- biologically important bonds

Final Exam

• Chapters 3 and 4• Main Concepts: Chemistry of Life– Acids, Bases, and pH scale– Functional Groups

• Vocabulary– Enantiomers

Final Exam

• Chapter 5• Main Concepts: Organic Molecules– Proteins– Nucleic Acids

• Vocabulary:– Denaturation

Protein Structure• Primary Structure: Unique sequence of amino acids:

sequence is determined by genetic material

• Secondary Structure: coiling /folding as a result of hydrogen bonding

• Tertiary Structure: 3-D shape due to bonding of R-groups

• Quaternary Structure: association of 2 or more polypeptides

Final Exam• Chapter 6, 7, 8• Main Concepts: Cells– Cell Theory– Plasma Membrane Structure

• Active vs Passive Transport

– Competitive Inhibitors• Vocabulary:– Gap Junctions– Eukaryotes and Prokaryotes– Hypertonic, Hypotonic, Isotonic– Uniport, Symport

Introduction• Cell is smallest functional unit of life• Cell theory:

–all organisms composed of cells–all existing cells arise from pre-existing cells

• There are two main types of cells: – Prokaryotes (lack nucleus)– Eukaryotes (true nucleus)

• Common characteristics of all cells:– cell contents surrounded by plasma membrane– cytoplasm consists of semifluid matrix– organelles are embedded in cytoplasm– contain genes in the form of DNA

Cell Membrane Structure

• Phospholipids of membranes form bilayers– phospholipids have polar “head” and nonpolar

“tail”– form stable bilayer in water with heads out and

tails in– hydrophobic interior forms barrier to hydrophilic

molecules

Membrane Function

• Water balance between cells and surroundings critical– cell membranes semi-permeable

– cells in isotonic solution do not change size -no osmosis

– cells in hypotonic solution gain water

– cells in hypertonic solutions lose water

Final Exam

• Chapters 9 and 10• Main Concepts: Energy Production– Cellular Respiration– Photosynthesis

• Vocabulary• Autotrophs • Heterotrophs• Fermentation

• Photosynthesis– Occurs in chloroplasts of

autotrophs– Uses energy from

sunlight to fix carbon dioxide into organic molecules (glucose)

• Cellular Respiration– Occurs in mitochondria– Glucose is broken down

yielding energy (ATP)

Overview of Energy Production

Final Exam

• Chapters 12 and 13• Main Concepts: Cellular Reproduction– Mitosis– Meiosis

• Vocabulary– Homologous Chromosomes– Sister Chromatids– Crossing Over

Mitosis vs Meiosis

Meiosis and Genetic Diversity

Natural selection results in the accumulation of genetic variations favored by the environment

Sexual reproduction contributes to the genetic variation in a population, which originates from mutations, through multiple processes:1. Independent orientation of chromosomes2. Random Fertilization3. Homologous chromosomes can have different versions

of genes4. Crossing Over

Final Exam Review• Chapters 14 and 15• Main Concepts: Patterns of Inheritance• Gregor Mendel• Punnett Square– 1 trait– 2 traits– Sex-linked

• Chromosome Theory of Inheritance• Vocabulary:– Homozygous and Heterozygous– Alleles, genotypes, phenotypes– Dominant and recessive

Gregor Mendel• Gregor Mendel, Austrian monk– Documented a particulate

mechanism in the 1800s by experiments with garden pea plants

• 1860s- Studied inheritance patterns in pea plants– Character= heritable feature with multiple variations– Trait= each type of variation for a character – At this time, chromosomes and genes had not been

discovered yet• Used the term heritable factors to represent what we call a gene

Example: White Tigers

White male mated with orange female All cubs = orange

Aa Aa

Aa Aa

A A

a

a

Orange Female (AA)

Whi

te M

ale

(aa)

Genotype Probability:

100% Heterozygous

Dihybrid Cross

Sex-linked genes have unique patterns of inheritance

• Sex-linked gene= genes located on sex chromosomes– X chromosome has many genes unrelated to sex– Y chromosome has very few genes

• The SRY gene on the Y chromosome codes for a protein that directs the development of male anatomical features

• Females- 2 copies of X chromosome– Typical dominant-recessive relationship– Females can be carriers of sex-linked disorders

• Males- 1 copy of X chromosome– Only needs one copy of allele to express trait– Sex-linked disorders tend to affect mostly males

Genetics• Late 1800s- Mitosis and Meiosis described• Early 1900s- Scientists noticed similarities

between chromosome behavior and Mendel’s “heritable factors”

• Chromosome Theory of Inheritance: genes occupy specific loci on chromosomes and it is the chromosomes which undergo segregation and independent assortment during meiosis– The behavior of chromosomes during meiosis can

account for Mendel’s laws of segregation and independent assortment

Final Exam Review• Chapters 16 and 17• Main Concepts: DNA • DNA Structure• DNA Replication• Transcription and Translation• Genetic Code• Vocabulary:– Codon and Anticodon– Dominant and recessive

DNA= Deoxyribonucleic acid• Double helix structure– Nitrogenous bases pair in center, forming

hydrogen bonds – Strands are complementary• Adenine-Thymine• Cytosine-Guanine• Chargaff’s Rule

– A=T and G=C

– Strand are antiparallel

DNA Replication

• Purpose= copy genetic code• Occurs in nucleus• Occurs during S phase of cell cycle• Necessary for cellular division

Flow of Genetic Information

Transcription

DNA

RNA

Protein

Translation

Evolution of the Genetic CodeGenetic code is nearly universal…

From unicellular organisms….

..to multicellular animals

Second mRNA base

Firs

t mRN

A ba

se (5

end

of c

odon

)

Third

mRN

A ba

se (3

end

of c

odon

)

UUU

UUC

UUA

CUU

CUC

CUA

CUG

Phe

Leu

Leu

Ile

UCU

UCC

UCA

UCG

Ser

CCU

CCC

CCA

CCG

UAU

UACTyr

Pro

Thr

UAA Stop

UAG Stop

UGA Stop

UGU

UGCCys

UGG Trp

GC

U

U

C

A

U

U

C

C

CA

U

A

A

A

G

G

His

Gln

Asn

Lys

Asp

CAU CGU

CAC

CAA

CAG

CGC

CGA

CGG

G

AUU

AUC

AUA

ACU

ACC

ACA

AAU

AAC

AAA

AGU

AGC

AGA

Arg

Ser

Arg

Gly

ACGAUG AAG AGG

GUU

GUC

GUA

GUG

GCU

GCC

GCA

GCG

GAU

GAC

GAA

GAG

Val Ala

GGU

GGC

GGA

GGGGlu

Gly

G

U

C

A

Met orstart

UUG

G

Genetic code:-Redundant-Not Ambiguous

Final Exam Review

• Chapter 22• Main Concepts• History of Evolution of Species– Jean Baptiste Lamarck and Charles Darwin

• Theory of Evolution– Unifying theory of biology

• Natural Selection

Evolutionary Adaptations of Organisms• Evolution

– Change through time– Descent with modification– Genetic changes in population from generation to generation

• Adaptations– Inheritable characteristic– Gives organism better chance of survival and reproductive

success in a specific environment• Natural Selection

– Individuals with certain inheritable characteristics have better chance of survival and reproductive success compared to individuals without those characteristics

– Unequal reproductive success leads to accumulation of favorable characteristics in population

Theory of Evolution• Pattern of Evolution– Observations from natural world– Collected from variety of fields• Biology, geology, physics, chemistry

• Process of Evolution– Mechanisms causing change

• Unifying theory of biology– Explains and connects observations from natural

world

3 Key Points to Evolution by Natural Selection

• Individuals do not evolve, populations evolve– Evolution occurs as adaptations accumulate in populations

over several generations• Natural selection only works on heritable traits with

variation in the population– Acquired traits are not passed to offspring

• Evolution is not working towards a specific goal or “perfect” organisms– Natural selection results from an organism interacting with

a specific environment– Characteristics favorable in one environment may not be

favorable in another

Final Exam Review

• Chapter 22• Vocabulary– Vestigial structures– Homologous structures– Intrasexual Selection– Intersexual Selection– Sexual Dimorphism

Final Exam Review

• Chapter 23• Main Concepts• Types of Natural Selection• Limits of Natural Selection• Heterozygote Advantage• Microevolution• Hardy-Weinberg Principle

Evolution of a Population

• Types of Natural Selection– Directional Selection• Highest reproduction in one

extreme phenotype

– Stabilizing Selection• Highest reproduction of

intermediate phenotypes

– Disruptive Selection• Highest reproduction of two

extreme phenotypes• Often leads to speciation

Generations1 2 3

Heterozygote Advantage• Homozygous Dominant

– No sickle cell allele– Susceptible to malaria

• Homozygous Recessive– Sickle-cell disease– Resistant to malaria

• Heterozygotes= co-dominant alleles, both types of blood cells– Heterozygotes have decreased

symptoms of malaria and decreased symptoms of sickle-cell disease

– Higher survival

Limits of Natural Selection• Selection can only act on existing variation in a population.– New alleles do not appear when needed

• Evolution is limited by historical constraints.– Ancestral structures are adapted to new situations

• Adaptations are usually compromises.– One characteristic may be an adaptation in one situation, a

disadvantage in another• Natural selection interacts with chance/random events and

the environment.– Chance events can alter allele frequencies in population– Environment can change

Types of Evolution• Microevolution= change in the gene pool of a

population over many generations• 4 Methods of Microevolution– Mutations• May be deleterious or neutral

– Natural Selection• Process in which individuals with favorable inherited traits

are more likely to survive and reproduce

– Genetic Drift= chance events cause genetic changes from one population to the next

– Gene Flow= individuals or gametes move to a different population

Hardy-Weinberg Principle• When allele frequencies remain constant from

generation to generation, the population is in Hardy-Weinberg equilibrium

• Equations: Allele Frequencies: p + q = 1 Genotype frequencies: p2 + 2pq + q2 = 1

• Assumptions:– No natural selection– No mutation– No gene flow– Random mating– Large population

Final Exam Review

• Chapter 23• Vocabulary• Cline• Genetic Drift• Bottleneck effect• Founder effect• Gene Flow

Final Exam Review

• Chapter 24• Main Concepts• Speciation• Biological Species Concept• Reproductive Barriers– Pre-zygotic and Post-zygotic

• Macroevolution– Mass extinction and adaptive radiation

• New species can arise from reproductive isolation between populations – No migration or gene flow

• Process of one species separating into 2 or more species– Development of new species leads to biodiversity

• Allopatric Speciation vs. Sympatric Speciation

Speciation

• Biological Species Concept– Group of populations with potential for successful

breeding in nature and to create fertile offspring• Biological Species Concept is widely accepted

and used by biologists today• Some situations require alternative concepts:– Identifying new species in the fossil record– Identifying prokaryotes (reproduce asexually)

Defining a “Species”

Reproductive BarriersTwo Types of Barriers:1. Prezygotic Barriers= prevents mating or fertilization from

happening2. Postzygotic Barriers= happens after fertilization occurs,

prevents viable, reproductive offspring

• Macroevolution= change in groups above the level of species, often results in new taxonomic groups

• Methods of Macroevolution– Adaptive radiation= periods of change when many

new species originate from a common ancestor– Mass extinctions= large number of species go extinct

within a relatively short amount of time• Environmental change• 5 mass extinctions have occurred through geological time

with 50% or more species lost

– Plate tectonics and Continental drift= movement of Earth’s plates

Types of Evolution

Final Exam Review

• Chapter 24• Vocabulary– Speciation– Allopatric and Sympatric Speciation– Mass extinction– Adaptive radiation– Continental drift