Fundamentals of Biology Flatworm segment Flatworm segment Flatworm segment Chapter 4

Fundamentals of Fundamentals of BiologyBiologyFlatworm segment

Chapter 4Chapter 4

4.1 The Ingredients of 4.1 The Ingredients of LifeLifeThe Building BlocksThe Building Blocks

Organic compoundsOrganic compounds Molecules containing carbon (C), Molecules containing carbon (C),

hydrogen (H), & oxygen (O)hydrogen (H), & oxygen (O) Make life possibleMake life possible High-energy moleculesHigh-energy molecules Energy used to synthesizeEnergy used to synthesize Energy released in breakdownEnergy released in breakdown Four types of organic compoundsFour types of organic compounds


CarbohydratesCarbohydratessugarssugars

Glucose – metabolized for energyGlucose – metabolized for energy Starches – long chains of simple sugars Starches – long chains of simple sugars

used for energy storageused for energy storage Chitin – skeletal materialChitin – skeletal material Cellulose – cell structureCellulose – cell structure


ProteinsProteins Chains of amino acidsChains of amino acids Muscles are mostly made up of proteinsMuscles are mostly made up of proteins Enzymes – catalyze reactionsEnzymes – catalyze reactions Structural proteins – skin, hair, skeletonStructural proteins – skin, hair, skeleton HormonesHormones


LipidsLipids Fats, oils, & waxesFats, oils, & waxes Energy storage – more than twice as Energy storage – more than twice as

much as sugarmuch as sugar Water repellantWater repellant BuoyancyBuoyancy InsulationInsulation HormonesHormones

A 56-foot, 60-ton sperm whale died on a beach A 56-foot, 60-ton sperm whale died on a beach in Taiwan in January, 2004in Taiwan in January, 2004


Nucleic AcidsNucleic Acids Store and transmit the genetic information of Store and transmit the genetic information of

all living thingsall living things Long chains of subunits called nucleotidesLong chains of subunits called nucleotides DNA – instructions for the construction and DNA – instructions for the construction and

maintenance of an organism; the complete set maintenance of an organism; the complete set is called the genomeis called the genome

The nitrogen bases are sequenced into genes The nitrogen bases are sequenced into genes that code for a specific proteinthat code for a specific protein

RNA – helps DNARNA – helps DNA


4.1 The Ingredients of 4.1 The Ingredients of LifeLifeThe Fuel of LifeThe Fuel of Life

ATP – the molecule used to store energy; ATP – the molecule used to store energy; like a rechargeable batterylike a rechargeable battery

You use ~ 125 lbs./dayYou use ~ 125 lbs./day Organisms need to capture, store and Organisms need to capture, store and

use energyuse energy Most organisms use only two sets of Most organisms use only two sets of

reactionsreactions


Photosynthesis: Making the FuelPhotosynthesis: Making the Fuel Algae, plants, and some microorganismsAlgae, plants, and some microorganisms Capture the sun’s energy and use it to make glucoseCapture the sun’s energy and use it to make glucose The pigment chlorophyll captures the solar energyThe pigment chlorophyll captures the solar energy COCO22 + H + H22O O C C66HH1212OO66 (glucose) + O (glucose) + O22

We rely on photosynthesis for food and oxygenWe rely on photosynthesis for food and oxygen Organisms that photosynthesize are called autotrophsOrganisms that photosynthesize are called autotrophs Plants on land; bacteria and algae in the oceanPlants on land; bacteria and algae in the ocean


Photosynthesis: Making the FuelPhotosynthesis: Making the Fuel


Respiration: Burning the FuelRespiration: Burning the Fuel Both autotrophs and heterotrophs do itBoth autotrophs and heterotrophs do it Releases the energy from org. Releases the energy from org.

compoundscompounds Reverse of photosynthesisReverse of photosynthesis


Respiration: Burning the FuelRespiration: Burning the Fuel Both autotrophs and heterotrophs do itBoth autotrophs and heterotrophs do it Releases the energy from org. compoundsReleases the energy from org. compounds Reverse of photosynthesisReverse of photosynthesis Organic matter (glucose) + OOrganic matter (glucose) + O22 HH22O + COO + CO22

Similar to burning wood or oilSimilar to burning wood or oil Chemical energy captured in ATPChemical energy captured in ATP Aerobic – uses oxygen, more efficientAerobic – uses oxygen, more efficient Anaerobic – does not use oxygen, less Anaerobic – does not use oxygen, less

efficientefficient

Fluffy yeast rolls. Compliments of Fluffy yeast rolls. Compliments of anaerobic respiration.anaerobic respiration.


Primary ProductionPrimary Production Most of the glucose is used for fuel or Most of the glucose is used for fuel or

converted into other types of org. compoundsconverted into other types of org. compounds The organic matter autotrophs make is called The organic matter autotrophs make is called

primary productionprimary production Used by the organism for growth and Used by the organism for growth and

reproductionreproduction Autotrophs are also called producersAutotrophs are also called producers


Primary ProductionPrimary Production Most of the glucose is used for fuel or Most of the glucose is used for fuel or

converted into other types of org. compoundsconverted into other types of org. compounds The organic matter autotrophs make is called The organic matter autotrophs make is called

primary productionprimary production Used by the organism for growth and Used by the organism for growth and

reproductionreproduction Autotrophs are also called producersAutotrophs are also called producers


The Importance of NutrientsThe Importance of Nutrients Vitamins, minerals and other substances are Vitamins, minerals and other substances are

needed to convert glucose into other organic needed to convert glucose into other organic compoundscompounds

Nitrogen for proteins & nucleic acidsNitrogen for proteins & nucleic acids Phosphorus for nucleic acidsPhosphorus for nucleic acids Silica (SiOSilica (SiO22) to make shells) to make shells Iron – necessary, but a limited resource in the Iron – necessary, but a limited resource in the

oceanocean

4.2 THE LIVING MACHINERY4.2 THE LIVING MACHINERY

Organic compounds are organized into functional units that are alive

4.2 THE LIVING MACHINERY4.2 THE LIVING MACHINERYCells and OrganellesCells and Organelles

Cell – basic unit of life Chemical energy

All organisms are made of cells Wrapped in a cell membrane

Cell is filled with jelly-like cytoplasm Organelles have specific jobs in the cell


Structurally Simple Cells: Prokaryotes Prokaryotes are primitive cells

Ancient, simple, small No membrane-bound organelles Bacteria

Prokaryotes have few structures: Cell wall – support Ribosomes – assemble proteins DNA – loose in the cytoplasm Flagella – locomotion


Structurally Complex Cells: Eukaryotes Eukaryotic cells are organized and complex

Larger than prokaryotes Have specialized organelles:

Nucleus – contains chromosomes (DNA) Endoplasmic reticulum – pathway for making of proteins and

other org. molecules for the cell Golgi apparatus – package and transport molecules Mitochondria – respiration center to provideenergy Flagella and cilia – for movement


Structurally Complex Cells: Eukaryotes Only in plant & algal cells

Chloroplasts – photosynthesis center Cell wall - support

Review the cellReview the cell

4.2 THE LIVING MACHINERY4.2 THE LIVING MACHINERYLevels of OrganizationLevels of Organization

A cell is self-contained and can carry out all the functions necessary for life Unicellular – all prokaryotes and some eukaryotes Multicellular – most eukaryotes

Human body has 100,000,000,000,000 cells In multicellular organisms cells specialize to perform different

tasks for the organism Cells that act together for a specific job are called tissues

Muscle, nervous, bone, blood, epithelial Tissues are organized into organs to carry out specific

functions Liver, kidney, heart, skin, brain

Organs act together in an organ system Skeletal, muscular, excretory, endocrine, digestive

4.2 THE LIVING MACHINERY4.2 THE LIVING MACHINERYLevels of OrganizationLevels of Organization

Organization exists outside the individual organism Species – one type of organism http://www.hemmy.net/2006/06/19/top-10-hybrid-animals/

Blue mussel Population – a group of one species

A bunch of blue mussels Community – several different populations that live and interact in

an area Blue mussels, crabs, barnacles, & chitons living on a rock

Ecosystem – the communities living together with the physical environment

Living on a rocky shore with seawater, air, temperature, sunlight, etc.

4.3 CHALLENGES OF LIFE 4.3 CHALLENGES OF LIFE IN THE SEAIN THE SEA

Marine organisms must cope with different problems than on land

They have evolved ways to adapt to their marine habitat

Most important is maintaining homeostasis

Keeping their internal condition normal regardless of the external condition

4.3 CHALLENGES OF LIFE IN THE SEA4.3 CHALLENGES OF LIFE IN THE SEASalinitySalinity

Marine organisms are immersed in a medium – sea water – that can greatly affect their cell function

Enzymes and organic molecules are sensitive to ion concentration (salinity)


Diffusion and Osmosis Dissolved ions move around in water Random movement spreads them out in an even distribution Results in diffusion – movement from high to low concentration When concentrations are different inside and outside a cell,

substances will move in/out by diffusion Salt from seawater will diffuse into the cell Nutrients will diffuse out of the cell

The cell membrane blocks block diffusion It’s selectively permeable – it allows only some substances to go

in/out

IN THE NEWSIN THE NEWS

Sacramento, CA 2007: A woman dies in Sacramento, CA 2007: A woman dies in a radio contest , “Hold your wee for a Wii”a radio contest , “Hold your wee for a Wii”

IN THE NEWSIN THE NEWS

Sacramento, CA 2007: A woman dies in Sacramento, CA 2007: A woman dies in a radio contest , “Hold your wee for a Wii”a radio contest , “Hold your wee for a Wii”

Diluted formula nearly kills Tampa baby Diluted formula nearly kills Tampa baby (2008)(2008)

SpongeBob spills salt on SpongeBob spills salt on Gary!Gary!


Diffusion and Osmosis Water is a small molecule and can fit

through the cell membrane It also diffuses from high low concentration If a cell has more solutes inside than

outside, water will stream in and swell the cell

If the seawater has more salt, water will leave and the cell will shrivel

This diffusion of water is called osmosis


Regulation of Salt and Water Balance Marine organisms have adapted ways to balance

water and salt Osmoconformers –their internal concentrations

change with the salinity of the seawater Live in a narrow range of salinity

Osmoregulators – control internal concentrations to avoid osmotic problems Can tolerate changes in salinity better Can change their internal concentrations to match

the seawater


Regulation of Salt and Water Balance Osmoregulators continued

Salt water fishes lose water by osmosis Drink water or reduce urine amount to replace lost water Excrete excess salts in the urine or through the gills

Freshwater fishes gain water by osmosis Don’t drink water or produce lots of urine Salt absorbed by gills


Regulation of Salt and Water Balance Some marine birds and reptiles have special glands to

get rid of excess salt Most algae have rigid cell walls that resist the swelling

caused by osmotic water gain

4.3 CHALLENGES OF LIFE IN THE SEA4.3 CHALLENGES OF LIFE IN THE SEATemperatureTemperature

Metabolic reactions speed up/slow down when temperature goes up/down

Metabolic rate doubles every 10oC At extreme temps most enzymes cease

to function Marine organisms are adapted to live in a

temp range Thus determining what regions of the

oceans they live

4.3 CHALLENGES OF LIFE IN THE SEA4.3 CHALLENGES OF LIFE IN THE SEATemperatureTemperature

Ectotherms – “cold blooded” lose their heat to the seawater Endotherms – “warm blooded” retain heat and keep their body

temp higher than the water Mammals, birds, and some large fishes

Poikilotherms – body temp changes with the temp of the seawater Incl. all ectotherms & endothermic fishes

Homeotherms – keep internal temp the same, regardless of outside temp Produce more heat as need to keep their metabolic activity

high Mammals & birds They need to eat more food Insulate their bodies with feathers, hair, and blubber

4.3 CHALLENGES OF LIFE IN THE SEA4.3 CHALLENGES OF LIFE IN THE SEASurface to Volume RatioSurface to Volume Ratio

Heat and materials exchange across the surface of an organism

The surface-to-volume ratio (S/V ratio) determines how rapidly this happens

As organisms get larger the volume grows faster than the surface area

Small organisms rely on diffusion Large organisms respiratory and excretory systems

4.4 PERPETUATING LIFE4.4 PERPETUATING LIFE

A species must reproduce or vanish from the planet

Produce a new offspring Pass on the genetic information

Tule perch•Live in fresh waters of Central California•Female gives birth to 15-40 young

4.4 PERPETUATING LIFE4.4 PERPETUATING LIFEModes of ReproductionModes of Reproduction

Cells reproduce through cell division Cell fission in prokaryotes; mitosis in

eukaryotes Results in identical daughter cells


Asexual Reproduction No partner Offspring are genetically identical – clones Most single-celled organisms reproduce this way Some multicellular organisms do:

Some sea anemones will split in half, making two smaller ones–fission

Some sponges develop growths that break off to become separate individuals – budding or vegetative reproduction


Sexual Reproduction Union of two separate gametes from two parents

Egg sperm

Meiosis divides the chromosomes in half; Fertilization combines them to form a full set again

A fertilized egg is called a zygote. It has DNA from both parents

This genetic recombination causes variation in the offspring Greatest advantage of sexual reproduction

The zygote divides by mitosis and eventually forms an embryo

May pass through a larval stage on the way to adulthood


Reproductive Strategies The goal of reproduction is to pass on the genes Varying reproductive strategies to get the same

result Broadcast spawning – release millions of eggs and

sperm into the water No parental care, most die

Have few offspring and invest more time and energy into their survival

Some use sexual and asexual reproduction Some species are hermaphroditic, both sexual

organs http://video.nationalgeographic.com/video/animals/invertebrates-animals/other-invertebrates/weirdest-flatworms/

4.5 DIVERSITY OF SEA LIFE4.5 DIVERSITY OF SEA LIFE

The vast diversity of organisms in the ocean came through millions of years of evolution

The gradual alteration of a species’ genetic makeup

4.5 DIVERSITY OF SEA LIFE4.5 DIVERSITY OF SEA LIFENatural Selection and AdaptationNatural Selection and Adaptation

Individual organisms show variation in how they: Find food, avoid being eaten, reproduce, find mates,

metabolize, etc. The best-adapted produce more offspring than the

others This process is called natural selection As their genes get passed on the favorable traits

become more common The population’s genetic makeup changes over

time as it adapts to its environment Populations either adapt to the changes in the

environment or become extinct

4.5 DIVERSITY OF SEA LIFE4.5 DIVERSITY OF SEA LIFEClassifying Living ThingsClassifying Living Things

To discuss the huge variety of life forms we must first classify them

The Biological Species Concept What is a species? A type of organism? A population with common characteristics that

can successfully breed with each other (fertile offspring)

If two populations cannot interbreed they are reproductively isolated


Biological Nomenclature Carolus Linnaeus introduced scientific naming

system Latin or Greek is used for naming Common names are confusing, scientific

names are used worldwide to precisely identify a species


Biological Nomenclature Organisms are identified with a two-word

name - Genus and species Blue whale – Balaenoptera musculus Fin whale – Balaenoptera physalus Minke whale – Balaenoptera acutorostrata


Phylogenetics: Reconstructing Evolution Organisms are grouped according to their

relatedness Related organisms share an evolutionary history, or

phylogeny They share a common ancestor

Look at fossil record,

anatomy, reproduction,

embryological development,

DNA, behavior, etc.


Phylogenetics: Reconstructing Evolution Organisms are grouped according to their

relatedness Related organisms share an evolutionary history, or

phylogeny They share a common ancestor

Look at fossil record,

anatomy, reproduction,

embryological development,

DNA, behavior, etc.


The Tree of Life Classifications have changed over time Started with two kingdoms – Animalia

and Plantae Then five kingdoms – added Fungi,

Monera, & Protista


The Tree of LifeBacteria Archaea ___________Eukarya___________ DOMAINS

Bacteria Archaea Protista Plantae Fungi Animalia SIX KINGDOMS

____Monera____ Protista Plantae Fungi Animalia FIVE KINGDOMS

__________________Plantae_________ Animalia TWO KINGDOMS


The Tree of Life Then three domain system


The Tree of Life Then three domain system

Domain Kingdom Phylum Class Order Family Genus Species

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Fundamentals of Biology Flatworm segment Flatworm segment Flatworm segment Chapter 4