Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 4 Lecture Slides

Life in the Ocean Fundamentals of Biology

The Essential Building Blocks of Life Just like water is a molecule, there are other molecules important to life. Just like water is a molecule, there are other molecules important to life. Four organic (contain carbon, hydrogen and oxygen) molecules make up living organisms: Four organic (contain carbon, hydrogen and oxygen) molecules make up living organisms:

Carbohydrates: Carbohydrates: –Used for energy.

–store energy to be used later (like starch found in plants and some algae. –used in structure such as chitin found in the shells of some animals (like crabs, lobsters and shrimp) or cellulose found in plants.

Proteins: Proteins: –Composed of amino acids Uses: hormones Structure immunity Internal transport

Lipids: Lipids: –Lipids are mainly hydrophobic (do not mix with water)

–many marine organisms use a coating of lipid to cover fur or feathers which provides an insulating layer. –Insulation (blubber) –Used for energy storage.

Nucleic Acids: Nucleic Acids: –Made of nucleotides. –DNA and RNA

Energy and Life In photosynthesis, plants, algae and other autotrophs use pigments to capture the energy in sunlight. In photosynthesis, plants, algae and other autotrophs use pigments to capture the energy in sunlight.

cellular respiration. cellular respiration. –Respiration consumes oxygen and produces carbon dioxide and water as by-products.

Producers: Organisms that photosynthesize Producers: Organisms that photosynthesize Consumers: Organisms that eat other organisms Consumers: Organisms that eat other organisms

Primary Production: The energy made by producers that becomes available to consumers. Primary Production: The energy made by producers that becomes available to consumers. Marine organisms are a major source of worldwide primary production Marine organisms are a major source of worldwide primary production

Types of Organisms Prokaryotic Organisms: Prokaryotic Organisms: –One cell –No nucleus –Posses ribosomes –Contain a circular ring of DNA –Bacteria are only living example

Eukaryotic Organisms Eukaryotic Organisms –DNA enclosed inside a nucleus –many specialized organelles (look at organelles in Fig. 4.8) –can be unicellular or multicellular

Levels of Organization in Living Organisms Atom – fundamental unit of all matter Atom – fundamental unit of all matter Molecule – two or more atoms chemically joined together Molecule – two or more atoms chemically joined together

Organelle – specialized features of cells Organelle – specialized features of cells Cell – basic unit of life Cell – basic unit of life

Tissue – group of cells functioning as a unit Tissue – group of cells functioning as a unit Organ – many tissues arranged into a structure with a specific purpose in an organism Organ – many tissues arranged into a structure with a specific purpose in an organism

Organ system – group of organs that work together Organ system – group of organs that work together Whole organism (individual) Whole organism (individual)

Levels of Organization in Living Organisms Population – group of organisms of the same species occurring in same habitat Population – group of organisms of the same species occurring in same habitat

Community – all species that exist in a particular habitat (ex: all the organisms on a coral reef) Community – all species that exist in a particular habitat (ex: all the organisms on a coral reef) Ecosystem – combination of the community and the physical environment Ecosystem – combination of the community and the physical environment

Diffusion and Osmosis Solutes (substances dissolved in water) will move from areas where they are more concentrated to an area where they are less concentrated Solutes (substances dissolved in water) will move from areas where they are more concentrated to an area where they are less concentrated This movement is called diffusion This movement is called diffusion

Diffusion of water is called osmosis Diffusion of water is called osmosis

Ocean Water has solutes (like salt) Ocean Water has solutes (like salt) –Too much water leaves animals’ bodies This can result in the death of cells This can result in the death of cells These organisms must find ways to deal with this diffusion and osmosis These organisms must find ways to deal with this diffusion and osmosis

Regulation of Solute/Water Balance Osmoconformers- Osmoconformers- –Internal concentration varies as the salinity in the water around them changes –Most can only tolerate a very narrow range of salinity

Osmoregulators Osmoregulators –Control their internal concentrations –Tolerate a wider range of salinities –How? Very little urine Very little urine Specialized glands to secrete salt Specialized glands to secrete salt

Temperature Control Ectotherms Ectotherms –Generate body heat metabolically, but cannot maintain constant internal body temperature Poikilotherms Poikilotherms –Body temperature mimics the surrounding environment –Examples: fish, reptiles

Endotherms Endotherms –Generate body heat metabolically. Homeotherms Homeotherms – maintain a constant internal temperature

Modes of Reproduction Asexual reproduction Asexual reproduction –One parent. –The young are clones of the parents.

Examples of Asexual Reproduction Examples of Asexual Reproduction –Fission – the splitting of one organism into two smaller organisms of equal size –Budding – the organism develops buds (small clones) that eventually break off and become another organism –Vegetative reproduction – a plant reproduces new individuals by sending an underground stem (rhizome) sideways from which new plants will sprout

Sexual reproduction Sexual reproduction –Parent individuals produce gametes (eggs or sperm) that combine to form a zygote.

Modes of Reproduction Broadcast spawning Broadcast spawning –release their eggs and sperm directly into the water at the same time –Some species time release to tides, moon phase, water temp. etc.

Internal fertilization, where a copulatory organ is used to insert sperm directly into the female’s reproductive tract Internal fertilization, where a copulatory organ is used to insert sperm directly into the female’s reproductive tract

Hermaphrodites – individuals that have male and female reproductive tissues Hermaphrodites – individuals that have male and female reproductive tissues

Evolution and Natural Selection Evolution is a change in the genetic make-up of a population over time Evolution is a change in the genetic make-up of a population over time Good traits (adaptations) in the ocean survive Good traits (adaptations) in the ocean survive –Swimming faster –Better camouflage –Swimming in schools

Natural selection strengthens the gene pool because only the best adaptations survive. Natural selection strengthens the gene pool because only the best adaptations survive.

Taxonomy Taxonomy is the science of classifying and naming organisms. Taxonomy is the science of classifying and naming organisms. Kingdom  Phylum  Class  Order  Family  Genus  Species Kingdom  Phylum  Class  Order  Family  Genus  Species

So, what defines a species? So, what defines a species? Common characteristics and the ability to breed successfully with other members of their species