BIO101 Exam 4

reductionism

the reduction of complex systems to simpler components that are more manageable to study

Eugenics

science dealing with improving hereditary qualities

Polymorphism

The coexistence of two or more distinct forms in the same population.

Mutation

change in a DNA sequence that affects genetic information; opposite of what gene normally signifies (example of white gene in fly)

biochemist (reductionist)

approach biology by breaking down systems into their fundamental chemical components and interactions, aiming to understand complex phenomena through the study of these simpler parts

geneticist

a person who studies genetics

How to build a pattern

1. a real pattern emerges from a hidden pre-existing pre-pattern or hidden pattern

2. a pattern is formed by collaboration or communication among individuals

natural mutation

Spontaneous changes in DNA occurring without human intervention

genetic mosaic

An individual with somatic regions that are genetically different from each other

genetic chimera

A tissue or organism comprised of cells of two or more distinct genotypes (only part of body is mutated)

Johann Wolfgang von Goethe

wrote Faust, Italian journey, the metamorphosis of plants

metamorphosis

change of form; transformation

Geothe's assertion from his works

proposed the (serially) homologous nature of each organs in plants

homologous

term used to refer to chromosomes in which one set comes from the male parent and one set comes from the female parent

parts of flower

sepals, petals, stamens, carpels

sepal

A leaflike structure that encloses the bud of a flower.

carpel

The female reproductive organ of a flower

stamen

Male reproductive part of the flower

petal

A colorful, leaflike structure of some flowers.

Goethe proposed what about metamorphosis of plants?

the floral organs are simply different manifestations of common underlying theme; an underlying organ was simply passing through a series of different forms

double-flowered

describes varieties of flowers with extra petals, often containing flowers within flowers

equivalence

the state of being equal or alike in value or importance

why do some flowers and flies have parts that appear to adopt mistakes identities?

segment identities are controlled by homeotic genes.

what is the function of scute in normal fly and where should it be expressed?

to make hair on the back of flies

genetic power of mutation

wait until flower makes genetic mistake and defective flower is generated

mutual inhibition

when one of the networks is active, it uses inhibitory neurotransmitters to suppress the other; expression of class A gene inhibits class C gene, and expression of class C inhibits class A

combinatorial

information technology can be combined in many different ways to successively develop more innovative products...A + B genes to make petals in a flower

homeotic transformations

Changes in the identity of an entire body segment, such as transforming a leg-bearing segment into a wing-bearing segment.

homolog

A gene related to a second gene by descent from a common ancestral DNA sequence

homeotic mutations

a mutation that causes one body part to be substituted for another

William Bateson

He was the first person to use the term genetics to describe the study of heredity and biological inheritance.

Edward B. Lewis

first to show that a specific group of genes controls the identities of body parts in the embryo of the common fruit fly.

Lewis' 3 mutations

wild type, bithorax, antennapedia

Segment identity

Specific characteristics assigned to body segments.

form

what makes up something

function

the special, normal, or proper activity of an organ or part

two kinds of similarity

homology and analogy

homology

similarity resulting from common ancestry

analogy

A comparison of two different things that are similar in some way

homolog structure

similar structure and position but different function

analog structure

similar function but different origin

vestigal structure

remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species.

evolutionary tree

a diagram that reflects evolutionary relationships among groups of organisms

convergent evolution

the evolution of similar, or analogous, features in distantly related groups

divergent evolution

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

are tasmanian and mexian wolf characteristics shared

no theres a placental mammal and marsupial mammal but both of those came from reptile common ancestor called egg laying mammal

are sharks, dolphins, and ichthyosaur from the same?

all three came from different ancestral background, shark from fish, ichthyosaur from reptile, and dolphin from mammal - example of convergent evolution generating analogous animals

why are analog structures from convergent evolution looking similar

their environment

what makes convergent evolution?

the environment, results in analog structures

what makes the differences in homolog structures?

the environment

what makes similarities in homolog structures?

common ancestor DNA

niche hypothesis??

if environment stays the same the similar kind of thing will evolve but maybe not the exact same thing??

parallel evolution

ex. native americans and ancestors in asia, both develop similar things in their civilization

why do forelimbs in humans and bats look similar but whales look more different?

natural selection in an aquatic environment resulted in changes to whale forelimb anatomy (flipper)

ortholog type of homolog

true, authentic homolog ex. front limb of animal A and front limb of animal B

paralog type of homolog

fake, pseudo homolog ex. front limb of animal A and rear limb of animal A

what causes ortholog and paralog?

abnormal duplication (A' and A'')

how do colors come from genes with no defects?

everything starts from red then gene 1 makes green then gene 2 makes blue

what would a mutation of gene 1 cause in colors

you only see red color

what would a mutation of gene 2 cause in colors

you only see red and green color (or maybe just green?)

how do you decide gene 1 is working first and gene 2 is working second

by the result of the absence of both genes (double mutation) without 1 it doesn'tt matter if you have gene 2 or not because only red appears

cytoplasmic polarity

molecules deposited into embryo from mother are distributed along gradients head-to-tail

gap genes

broad region gap differentiation; delete groups of adjacent segments

pair rule genes

affect alternate segments; delete same part of pattern in every other segment

segment-polarity genes

development of individual segments; affect polarity of segment - part of segment replaced by mirror image of part of another segment

maternal effect gene

phenotype expected from the genotype of the mother, irrespective of its own genotype

bicoid gene

a maternal effect gene that affects the front half of the body