BD & E EXAM 1

theory

explanatory, overarching explanation of natural phenomena’s ( predicts, testable, falsifiable, explanatory)

theory of biological evolution

descent with modification from a single common ancestor

homology

shared, derived trait that indicates common ancestry

where do new or derived traits come from?

random mutation but the patterns of evolution is not random

what’s an allele?

variant of a gene

heritable variation

leads to differential reproductive success results in changes in allele frequencies or evolution

biological fitness

the ability of individuals to produce viable offspring

Why is a parents fitness is not fully realized at birth of their offspring ?

Their biological fitness is effectively 0 until their offspring survives and reproduces

If a parents had 2 children and their children had two kids each what would number would the parents fitness be?

4 because each reproductive success is one unit of fitness

what is adaptation

heritable trait that increases fitness of individuals in a particular environment

example of homology

similarity with the # & arrangement of bone elements in tetrapod limbs and share similar DNA and body structures among different organisms that indicate common ancestry

how does adaptation allow individuals to have better offspring?

It increases the individuals survival and reproductive success, allowing them to produce offspring that are more likely to survive, reproduce, and inherit those advantageous traits.

random mutation

creates new traits and those that are the most helpful, individuals are more likely to survive and produce offspring

acclimation/ acclimatization

individuals physiological response to a changing environment (usually not permanent & never inheritable)

example of acclimation

move to a hotter climate and start sweating more. your body is just adjusting to help you cool down, the change is temporary and wont be inherited by your children

what does population evolve and individuals do not mean?

evolution happens in a population over generations, not a single person. individuals cant change genes from experiences or environments, population changes as certain traits become more common due to natural selection or mutation

why is evolution not goal oriented ?

evolution is a response to the environment. Changes happen randomly, through mutations, natural selection selects favorable traits to help individuals survive and reproduce in their current environment.

why does evolution not perfect organisms?

The environment keeps changing, natural selection is not goal oriented, and new traits come from random mutations.

natural selection

process that changes allele frequencies when certain heritable traits are associated with different levels of reproductive success

evolution

change in allele frequencies

directional selection

natural selection that favors extreme phenotype

stabilizing selection

natural selection that favors the average phenotype in the population and acts against extreme phenotypes

artificial selection

when humans actively and consciously select which individuals will be parents of the next generation.

LUCA

last universal common ancestor

two types of fossil records

extinction: species cease to exist

transitional form: species change from one form to another overtime

fossil records

any trace of and organism that lived in the past ex. footprints, teeth, shells

monophyletic group

an ancestor and all its descendants

why are older fossils replaced overtime by newer related species ?

it shows how life changes throughout time

all species are related to each other by common ancestry T or F

T

phylogenetic tree

diagram showing evolutionary relationships among organisms. no species are higher or lower than one another

no such thing as unrelated species T or F

T

central dogma

flow of genetic information DNA- RNA - protein

science

narrowly focused disciplines that seeks to pose answerable questions about nature

science can be defined by 3 things

1: real world: exist independent of us

2: can be understood by 5 sense

3: natural cause and effects

hypothesis

repeatability, access to data

scientific hypothesis is

testable

falsifiable

predictive power

guiding statements for research

law

constant phenomenon or process

testable, falsifiable, predictive power

Homoplasy

independent evolution of similar traits in distinct species that do not share a recent common ancestor

Convergent evolution

independent evolution of similar features in species from different lineages, driven by similar environmental pressures rather than common ancestry