ENVIRONMENTAL SCIENCE

Chapter 4 The Organization of Life

4.3 The Diversity of Living Things

4.3 The Diversity of Living Things Objectives

• Name the six kingdoms of organisms and identify two characteristics of each.

• Explain the importance of bacteria and fungi in the environment.

• Describe the importance of protists in the ocean environment.

• Describe how angiosperms and animals depend on each other.

• Explain why insects are such successful animals.

Introduction• Most scientists classify the tremendous

diversity of life on Earth into six kindoms.– Archaebacteria– Eubacteria– Fungi– Protists– Plants– Animals

• Members of these six kingdoms get their food in different ways and are made of different types of cells – the basic unit of life.

Bacteria• Bacteria are microscopic, unicellular

organisms that normally have a cell wall, and reproduce by dividing in half.

• Both kingdoms of bacteria, archaebacteria and eubacteria, lack a true nucleus.

• Bacteria live in every environment on Earth from hot springs to the digestive tract of animals.

• Most bacteria belong to the eubacteria• Some kinds of bacteria are directly involved

in breaking down waste materials, feces, and dead plants and animals.

Bacteria• The recycling of elements and fixation of

nitrogen (from atmospheric nitrogen to a usable form for plants) are extremely important in maintaining a proper environment.

• Bacteria also allow many organisms, including humans, to extract certain nutrients from their food.

• Escherichia coli, found in the intestines of humans and other animals, is essential in the digestion of food and the release of certain vitamins.

Scanning electron micrograph of E. coli (above).

Oscillatoria, a common cyano-bacterium in ponds and lakes.

Fungi• The fungi are organisms with cells that have

nuclei, cell walls, and no chlorophyll.• The mushroom is simply a reproductive

structure of a fungus.• The rest of the fungus is an underground

system of hyphae that absorb food from decaying organisms underground.

• All fungi are heterotrophs because they absorb their food from their surroundings.

• Fungi release chemicals that break down food sources so that the nutrients can then be absorbed.

Fungi

• Fungi play an important role in the environment by breaking down the remains of dead plant and animal matter.

• Some fungi cause diseases, such as athlete’s foot.

• Other fungi are used in baking food, such as yeast, or eaten as a delicacy – like truffles.

Protists• Kingdom Protista is a large, very diverse group

of organisms that includes most of the unicellular eukaryotic organisms as well as algae that can include very large organisms such as kelp.

• Diatoms, unicellular marine algae with cell walls of silica that are responsible for much of the atmosphere’s free oxygen, are protists.

• Many parasitic forms of protists, such as Plasmodium sp. are causative agents of human disease.

• Spirogyra is an algae commonly seen as pond scum in many freshwater ponds and lakes.

Plants• Plants are multi-cellular autotrophs, have cell

walls made of cellulose, and they normally make their own food through photosynthesis.

• Most plants live on land where they receive sunlight, oxygen, and carbon dioxide from the atmosphere and minerals and water are normally extracted from the ground.

• Roots provide anchorage for most plants and gather much needed water from the ground.

• Leaves normally intercept light energy and convert it to chemical energy and provide an avenue for gas exchange.

Plants• Vascular tissues provide for transport

of water and nutrients for the plant as well as provide support for the plant.

• The earliest plants on land had no vascular tissue and swimming sperm, therefore, they could not grow very tall or be far from water.

• Liverwort is an example of one such non-vascular plant.

• Club mosses and ferns were some of the first plants to have vascular tissue.

Plants• Gymnosperms are woody plants that have

seeds which are not enclosed in fruits.• Many of the cone-bearing gymnosperms are

called conifers.• Gymnosperms produce pollen, a design that

protects the sperm and moves it from one plant to another.

• The developing plants are protected from drying out by the design of the seed.

• A conifer’s needle-like leaves protect the plant from drying out by losing too much water.

Plants• Angiosperms, flowering plants that produce seeds

in fruit, make up most of today’s land plants.• The flower is the reproductive structure of

angiosperms.• Some angiosperms have small flowers that

produce pollen carried by wind or water currents.• Some angiosperms depend on insect or other

animal vectors for pollination.• Also, some animals will eat the fruit of

angiosperms and deposit the seed later as the animal releases excrement, thus dispersing the plant.

• Human populations depend heavily on the flowering plants that produce grain crops such as wheat and rice.

Animals

• Animals are multi-cellular heterotrophs with no cell walls.

• Animals often move about in their environment in at least one stage of their life.

• Invertebrates are animals that have no backbone.

• Some invertebrates live attached to a hard substrate at the bottom of the ocean and filter particles of food from the water.

• The larvae of many sessile organisms are motile – they swim about and settle in another place.

Animals• Invertebrates also include motile and diverse

groups such as the mollusks and insects.• There are more insects on Earth than any

other type of animal.• Insects have an external skeleton, they can

move quickly, reproduce in great numbers, and most can fly.

• Because of their small size, they can live on little food and hide from predators in small areas.

• Many insects have coevolved with species of plants which they pollinate.

Darwin’s orchid (right) has a nectar chamber almost 11 inches deep. Based on this, a species of moth was predicted to exist that was discovered 40 years later.

Acacia trees and ants (left) have developed a mutalistic relationship.

Animals• Vertebrates are animals that have

backbones.• The first vertebrates were fish, however, all

biomes have vertebrate representatives that can be found in the water, on land, and in the air.

• Amphibians are either partially or completely aquatic.

• The development of the amniotic egg and a skin that retains moisture allowed the first amniotes (reptiles) to truly colonize land biomes in the Paleozoic Era.

Animals• Birds and mammals (and

dinosaurs???) have evolved a means of homeostasis regulation that allows for a fairly constant internal body temperature with little influence from the external environment.

• The internal regulation of body temperature allowed for colonization of previously inhospitable habitats.

References• Six Kingdoms of Classification -

http://darkwing.uoregon.edu/~jensrud/class_log.html

• Escherichia coli - http://res2.agr.ca/Lethbridge/emia/SEMproj/ecoli_e.htm

• Osciallatoria - http://www.rvt.com/~lucas/school/cyano.html

• Truffles Pig - http://alum.mit.edu/ne/whatmatters/200107

References• Truffles -

http://www.e-rcps.com/pasta/rcp/p_stuv/truff_blk.shtml

• Athlete’s Foot - http://www.foothealthcare.com/html/footprobs/problem/athletefoot.htm

• Spyrogira - http://www2.volstate.edu/rbarber/Labillustrations.htm

• Kelp - http://www.pbs.org/oceanrealm/seadwellers/cathedraldwellers/kelp1.html

References• Amoeba proteus -

http://www.oberlin.k12.oh.us/talent/isp/reports2002/amoebaproteus/proteus.htm

• Liverworts - http://masseynews.massey.ac.nz/magazine/2003_Nov/stories/profile-2.html

• Vascular Tissue - http://www.wappingersschools.org/RCK/staff/teacherhp/johnson/visualvocab/page9.html

• Australian Tree Fern - http://www.teachersparadise.com/ency/en/wikipedia/v/ve/vernation.html

References• Pine Cone -

http://www.erin.utoronto.ca/~w3env100y/env/ENV100/sci/biodiversity_03.htm

• Cycad Cone - http://www.cdutcm.edu.cn/jpkc/yyzw/wwwroot/botany/taxon/gymnosperm?D=D

• Gymnosperms - http://www.cneccc.edu.hk/subjects/bio/album/Chapter2/PINE_GYMNOSPERM.html

• Angiosperm Flower - http://faculty.uca.edu/~johnc/evolution_and_diversity1441.htm

References• Crinoid -

http://oceanexplorer.noaa.gov/explorations/04fire/logs/april02/media/crinoid.html

• Halocynthia roretzi (Sea Squirt)- http://www.lib.noaa.gov/korea/main_species/sea_squirt.htm

• Ant & Acacia Mutualism - http://web.fccj.org/~dbyres/ant1.html

• Darwin’s Orchid - http://faculty.washington.edu/jrw/110/darorch.htm