GENERAL BIOLOGY

• absolute dating Determines Actual age of fossils
• Fossil Records provide an actual record of Earth’s past life forms. Change over time can be seen in the fossil record.
• Paleontologist- scientist who studied fossils.
• Biogeography is Organisms from a prior geographic region that were closely related but different species travelled into surrounding habitats and evolved in these far apart geographic regions.
• DNA/ Protein sequences are All living things share the same genetic structure (DNA & RNA)
• Homologous Structures Structures found in organisms that share a common ancestry but have

  since evolved for different functions.
• Analogous Structure Refers to the parts of living organisms that have different structures

  but similar functions.
• • ANALOGOUS ANIMALS: Bat,Bird,Butterfly and Shark(Fish), Penguin(Bird), Dolphin(Mammal)
• • Vestigial Structure Refers to the structures that are reduced in size and function.
  • Non-functioning parts of living organisms.
• Embryology Early on in development vertebrate embryos are strikingly similar.

  Each has a tail, Pharyngeal pouches, buds
• WHAT IS FOSSILS?

  Evidence of organisms that lived in

  the past.

  they can be actual remains like

  bones, teeth, shells, leaves, seeds,

  spores or traces of past activities

  such as animal burrows, nests, and

  dinosaur footprints or even the

  ripples created on a prehistoric

  shore.
• Unaltered preservation- small organism or past trapped in amber, hardened plant sap is observed.
• Per mineralization/ Petrification- the organic contents of bone and wood are replaced by silica, calcite, forming a rock-like fossils.
• Replacement- hard parts are dissolved and replace by other minerals.
• Carbonization/ coalification – the other elements are ionized and only the carbon remained.
• Recrystallization- the hard parts are converted into more stable minerals or small crystals turned into larger crystals.
• Authigenic preservation- molds and casts are formed after most of the

  organisms have been destroyed or dissolved.
• MOLDS

  Description: impression made in a

  substrate = negative image of an

  organism.

  A hollow area in sediments in the

  shape of an organism.

  Ex. Shells.
• CASTS

  Description: when a mold is filled in.

  Solid copy of the shape of an

  organisms.

  Ex. Bones and teeth
• PETRIFIED

  Description: Organic material is

  converted into stone.

  Ex. Petrified trees; coal balls

  (fossilized plants and their tissues,

  in round ball shape).
• ORIGINAL REMAINS

  Description: Preserved wholly (

  frozen in ice, trapped in tar pits,

  dried/ dissected inside caves/

  fossilized resin.

  Ex. Woolly mammoth
• CARBON FILM

  Description: Carbon impression in

  sedimentary rocks.

  Ex. Leaf impression on the rocks.
• TRACE/ ICHNOFOSSILS

  Description: Record the

  movements and behaviors of the

  organism.

  Ex. Trackways, toothmarks,

  gizzard rocks, corpolites.
• RELATIVE DATING is Based upon the study of layers of rocks.

  Does not tell the exact age: only compare fossils

  as older or younger, depends on their position in

  rock layers.

  Fossils in the uppermost rock layer/ strata are

  younger while those in the lowermost deposition

  are oldest.
• LAW OF SUPERPOSITION:

  Sedimentary layers are deposited

  in a specific time- youngest rocks

  on top, oldest rocks at the bottom.
• LAW OF ORIGINAL

  HORIZONTALITY: Deposition of

  rocks happen horizontally- tilting,

  folding, or breaking happened

  recently,
• LAW OF CROSS-CUTTING RELATIONSHIPS: If an igneous

  intrusion or a fault cuts through existing rocks, the intrusion/fault is

  YOUNGER than the rock it cuts through.
• ABSOLUTE DATING

  Determines the actual age of the fossil

  Through radiometric dating, using radioactive

  isotopes carbon-14 and potassium-40

  Considers the half-life or the time it takes for half

  of the atoms of the radioactive element to decay

  • The decay products of radioactive isotopes is

  stable atoms.
• What is Evolution?

  It deals with the starting point of life and process of alteration of

  simple life forms to complex.

  Some organisms may change or appear, and some are lost or become

  extinct.

  It refers to gradual change in species eventually resulting to genetic

  adaptation from their surrounding.
• French botanist and naturalist

  Jean Baptiste Lamarck

  proposed that life evolves or

  changes.
• LAMARCK also explained Evolution is

  a process of adaption.
• Theory of Use and Disuse – the

  continued use of a part of a living

  organisms strengthens it and the

  continued disused of an organ

  deteriorates it until it disappears. The

  size of the organ is determined by

  the degree to which it is used.
• Theory of Need – it refers to the

  production of a new organ that arises

  according to the needs of an

  organisms.
• Theory of Inheritance of

  Acquired Characteristics – it refers

  to the characteristics of the parents

  that are being inherited or can be

  passed to its offspring.
• British naturalist and biologist Charles

  Darwin proposed his theory of evolution by

  natural selection.
• Survival of the fittest (natural selection) It

  is not the strongest of the species that

  survives, nor the most intelligent, but the one

  most responsive to change.
• THEORY OF EVOLUTION BY

  NATURAL SELECTION

  Their beaks have evolved over time

  to be best suited to their function.

  For example, the finches who eat

  grubs have a thin extended beak to

  poke into holes in the ground and

  extract the grubs.
• THEORY OF EVOLUTION BY

  ARTIFICIAL SELECTION

  Is the process by which humans

  choose individual organisms with

  certain phenotypic trait values for

  breeding.
• GENE FLOW

  movement of genes into or out of a

  population.

  Introduction of genetic material (by

  inbreeding) from one population of

  a species to another,
• GENETIC DRIFT

  is the change in frequency of an

  existing gene variant in the

  population due to random chance.

  Genetic drift may cause gene

  variants to disappear completely and

  thereby reduce genetic variation.