Title

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Introducción aBiología

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13.7 µm

All organisms maintain an internal order that is separated from the external environments:-All organisms are made of cells-The simplest unit of organization is the cell.-Cells come from pre-existing cells via cell division

Energy is required to maintain internal order.

- Chemical reactions involved in the breakdown and synthesis of cellular molecules are collectively

known as metabolism.

Living organisms most respond to a changing environmentand maintain stable internal conditions through homeostasis:

All organisms growth and develop

- Growth produces more or larger cells- Development produces organisms with a

defined set of characteristics.

Organisms have a finite life span

- To sustain life over many generations, organisms must reproduce

- Due to the transmission of genetic material, offspring tend to have traits like their parents

Organisms evolve at the population level

- Populations of organisms change over the course of many generations.

- Evolution results in traits that promote survival and reproductive success.

a: © Biophoto Associates/Photo Researchers; b: © Alexis Rosenfeld/Photo Researchers; d: © Adam Jones/Visuals Unlimited;e: © Patti Murray/Animals Animals; f: © Paul Hanna/Reuters/Corbis; g: © AP Photo/Mehgan Murphy, National Zoo

7 characteristics common to life

Fig. 1.6Molecules

Levels of organization

AtomsMacromolecules

cells

Tissue

organs

organism

Population

Community

ecosystemBiosphere

Why is important the study of the biodiversity?

What’s biodiversity?

Why is important to protect biodiversity?

Diversity??

Species!!!

Why? • Plants, animals and microorganisms may help us

• Medicines• Food• Industrial products

•Understand essential services provided by ecosystems•Is fun!!!

Biodiversity (United Nations Convetion on Biological Diversity)•“The variability among living organisms from all sources”

Fig. 1.7

All life forms can be placed into 3 large domains

Bacteria (prokaryotic)

• Microorganism• Cell structure relatively simple Archaea (prokaryotic)

• Microorganism• Cell structure relatively simple

Eukarya

• Larger cells with internal components (eukaryotic)• All have cell nucleus in which the genetic material

is encaged by a membrane

Bacteria Archaea Eukarya

Common ancestral community of primitive cells

AnimalsFungi Plants Protists

Horizontal gene transferVertical evolution

KEY

Traditionally Eukarya was subdivided in 5 kingdoms

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(c) Domain Eukarya: Unicellular and multicellular organisms having cells with internal compartments that serve various functions.

(a) Domain Bacteria: Mostly unicellular prokaryotes that inhabit many diverse environments on Earth.

(b) Domain Archaea: Unicellular prokaryotes that often live in extreme environments, such as hot springs.

Protists: Unicellular and small multicellular organismsthat are now subdivided into seven broad groups basedon their evolutionary relationships.

Plants: Multicellular organisms that can carry outphotosynthesis.

Fungi: Unicellular and multicellular organisms that have a cell wall but cannot carry out photosynthesis. Fungi usually survive on decaying organic material.

Animals: Multicellular organisms that usually have a nervoussystem and are capable of locomotion. They must eat otherorganisms or the products of other organisms to live.

a: © Dr. David M. Phillips/Visuals Unlimited; b: © B. Boonyaratanakornkit & D.S. Clark, G. Vrdoljak/EM Lab, U of C Berkeley/Visuals Unlimited;c(1): © Dr. Dennis Kunkel/ Visuals Unlimited; c(2): © Kent Foster/Photo Researchers; c(3): © Carl Schmidt-uchs/Photo Researchers; c(4): © Fritz Polking/Visuals Unlimited

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Examples

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species

Eukarya

Animalia

Chordata

Actinopterygii

Perciformes

Pomacentridae

Amphiprion

ocellaris

2,000 mya

600 mya

525 mya

420 mya

80 mya

~ 40 mya

~ 9 mya

> 3 mya

> 5,000,000

> 1,000,000

50,000

30,000

7,000

360

28

1

Taxonomicgroup

Clownanemonefishis found in

Approximate timewhen the commonancestor for thisgroup arose

Approximatenumber ofmodern speciesin this group