BIO FINAL

Gregor Mendel

scientist that discovered how traits were passed down from one generation to the next (garden peas)

Law of Dominance

Some alleles are dominant and some are recessive

law of independent assortment

the law that states that genes separate independently of one another in meiosis

Law of Segregation

Mendelian law stating that two alleles for each trait separate during meiosis

blood types

A, B, AB and O. Type O is the universal donor and AB blood is known as the universal recipient.

Dominant

An allele that is always expressed

Recessive

An allele that is masked when a dominant allele is present

Punnett Square

diagram showing the gene combinations that might result from a genetic cross

Probabilty

the likehood of an event happening

FOIL method

First, Outer, Inner, Last

DNA

double- stranded nucleic acid that contains the sugar deoxyribose acid

RNA

single-stranded nucleic acid that contains the sugar ribose

tRNA

transfer RNA; type of RNA that carries amino acids to the ribosome

rRNA

ribosomal RNA; type of RNA that makes up part of the ribosome

mRNA

messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome

geneotypes

genetic makeup

Phenotype

An organism's physical appearance, or visible traits

Homozygous

An organism that has two identical alleles for a trait

Heterozygous

An organism that has two different alleles for a trait

homozygous recessive

Both alleles (factors) for a trait are the same and recessive (aa)

homozygous dominant

Both alleles (factors) for a trait are the same and dominant (AA)

cell cycle

series of events that cells go through as they grow and divide

s phase of interphase

chromosome replicate and DNA synthesizes

Metaphase

second phase of mitosis, during which the chromosomes line up across the center of the cell

mitosis

part of cell division during which the cell nucleus divides

meiosis

process by which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell

sex chromosomes

X and Y chromosomes

Translation

when genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm

transcription

the organic process whereby the DNA sequence in a gene is copied into mRNA

introns

sequence of DNA that is not involved in coding for a protein

exons

Coding segments of eukaryotic DNA

splicing

the process of removing introns and reconnecting exons in a pre-mRNA

autosomal dominant examples

Huntington's disease. Marfan syndrome. Achondroplasia

autosomal recessive examples

cystic fibrosis, sickle cell anemia, and Tay-Sachs disease

x linked recessive ex

color blindness and hemophilia

x linked dominant ex

Fragile X

hybrid

anything of mixed origin

purebreed

Having two of the same genes for a trait

test cross

breeding that can be used to determine an organism's genotype

monohybrid

A cross between individuals that involves one pair of contrasting traits

dihybrid

A cross between individuals that have different alleles for the same gene

trait

A characteristic that an organism can pass on to its offspring through its genes

genetic mutations

Changes in the genetic material of cells that passes from one generation to another

diploid (2n)

an organism or cell having two sets of chromosomes or twice the haploid number

haploid

an organism or cell having only one complete set of chromosomes

karyotype

A picture of all the chromosomes in a cell arranged in pairs

autosomes

Any chromosome that is not a sex chromosome

amino acids

building blocks of proteins

protein synthesis

Forming proteins based on information in DNA and carried out by RNA

Codons and Anticodons

codon is mRNA and anti codon is tRNA

start codons

signals the start of translation and the amino acid methionine

stop codons

UAA, UAG, UGA

Pedigree: Autosomal Recessive

Person needs 2 copies of gene/allele to express phenotype. Male & Female equally likely to express trait, Generally SKIPS generations, Trait appear in offspring of unaffected parents

Pedigree:Autosomal Dominant

Every Generation, Males/Females, No unaffected parents having affected children

Gene

A segment of DNA on a chromosome that codes for a specific trait

Locus

Location of a gene on a chromosome

Multiple alleles

three or more forms of a gene that code for a single trait

alleles

Different forms of a gene

codominance

A condition in which neither of two alleles of a gene is dominant or recessive

incomplete dominance

Situation in which one allele is not completely dominant over another allele

chromosome

A threadlike, gene-carrying structure found in the nucleus. Each chromosome consists of one very long DNA molecule and associated proteins.

Centromere

Region of a chromosome where the two sister chromatids attach

chromatids

two identical chromosomes that split and contain the same genetic material

histones

protein molecule around which DNA is tightly coiled in chromatin

telomere

repetitive DNA at the end of a eukaryotic chromosome

homologus chromosomes

Chromosomes that have the same sequence of genes and the same structure

point mutation

gene mutation in which a single base pair in DNA has been changed

silent mutation

alters a base but does not change the amino acid

missense mutation

A base-pair substitution that results in a codon that codes for a different amino acid

nonsense mutation

changes a normal codon into a stop codon

frameshift mutation

mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide

Pedigree: X-linked Recessive

•Appears more in males than females, Does NOT pass from father to son, Male passes his one allele to all daughters as carrier, who will pass trait to ½ of her sons, Often skips a generation

Pedigree- X Liked Dominant

This kind of trait affects both males and females equally and does not skip generations., All affected males have an affected mother, All affected females have an affected father or mother, All female progeny of an affected male are affected.

charles darwin

English natural scientist who formulated a theory of evolution by natural selection

Carolus Linnaeus

developed binomial nomenclature, father of taxonomy

James Hutton

father of modern geology, gradualism

Charles Lyell

Uniformitarianism, wrote principles of geology

Thomas Malthus

an English economist who argued that increases in population would outgrow food

Alfred Wallace

Came up with the idea of natural selection to explain evolution, joint published with Darwin

Lamarck

French naturalist who proposed that evolution resulted from the inheritance of acquired characteristics (1744-1829)

Erasmus Darwin

Thought all living things came from a common ancestor

Artistole

Greek philosopher and scientist

HMS Beagle

Darwin's ship

Galagoes Islands

Darwins main motivation

Gene Pool

All the genes, including all the different alleles for each gene, that are present in a population at any one time

genetic drift

A change in the allele frequency of a population as a result of chance events rather than natural selection

speciation

Formation of new species

species

A group of similar organisms that can breed and produce fertile offspring.

gene flow

movement of alleles from one population to another

bottleneck

process in which a large population declines in number, then rebounds

common descent

principle that all living things were derived from common ancestors

macroevolution

large-scale evolutionary changes that take place over long periods of time

microevolution

small-scale evolution, such as changes in allele frequency, that occurs from one generation to the next

convergent evolution

when two different organisms develop similar traits

divergent evolution

when a species sharing a common ancestor become more different over time

natural selection

A natural process resulting in the evolution of organisms best adapted to the environment

artificial selection

Selection by humans for breeding of useful traits from the natural variation among different organisms

adaption

A trait that helps an organism survive and reproduce

fossils

Preserved remains of once-living organisms

camouflage

the act of concealing the identity of something by modifying its appearance