Transcript Garrison Oceanography 7e Chapter 13

Oceanography
An Invitation to Marine Science, 7th
Tom Garrison
Chapter 13
Life in the Ocean
13.1: Life on Earth is Notable for Unity
and Diversity
• Diversity: 100 million different species
• Unity: all share the same mechanisms for capturing
and storing energy, manufacturing proteins, and
passing on information to the next generation
• In a sense, all life on Earth is fundamentally the
same – it’s just packaged in different ways.
13.2: The Flow of Energy Through Living Things
Allows Them to Maintain Complex Organization
• Energy: the capacity to do work
– Living matter can’t function without it
• First law of thermodynamics (energy):
living organisms can’t create new energy,
just transforms one kind to another.
– Example: plant = light energy to
chemical energy
– Example: animal = chemical energy
into energy of movement
13.2: The Flow of Energy Through Living Things
Allows Them to Maintain Complex Organization
• Second law of thermodynamics
(energy): energy becomes run down as
time passes and increases in
disorganization
– Example: radiating of waste heat
13.2: Energy Can Be Stored through
Photosynthesis
• Most of the energy used by marine organisms to make
food comes from the sun.
• Photosynthesis is the process used by most
producers to convert the sun’s energy to food energy.
• Chlorophyll: part of the plant that absorbs the light
energy
13.2: Energy Can Be Stored through
Photosynthesis
In photosynthesis, energy from sunlight is used to bond six
separate carbon atoms (derived from carbon dioxide) into a
single energy-rich, six-carbon molecule (the sugar glucose). The
pigment chlorophyll absorbs and briefly stores the light energy
needed to drive the reactions. Water is broken down in the
process and oxygen is released.
13.2: Energy Can Be Stored through
Photosynthesis
The flow of energy through
living systems:
• Light to producers
• Producers to consumers
• Consumers into space
• At each step, energy is
degraded (transformed
into a less useful form).
Sun
Producers
Photosynthesizers:
Green plants
and algae, and
specialized
bacteria
Consumers
Respirers:
Animals and
decomposers and
plants at night
To space
Stepped Art
Fig. 13-3, p. 347
13.2: Energy Can Be Stored through
Chemosynthesis
• Chemosynthesis is the production of food from
inorganic molecules in the environment.
13.2 Energy Can Also Be Stored through
Chemosynthesis
A form of
chemosynthesis. In
this example, 6
molecules of oxygen
and 24 molecules of
hydrogen sulfide to
form glucose. (other
products include 24
sulfur atoms and 18
water molecules.) The
energy to bond
carbon atoms into
glucose comes from
breaking the chemical
bonds holding the
sulfur and hydrogen
atoms together in
hydrogen sulfide.
13.1-13.2 Concept Questions
1.
2.
3.
4.
5.
6.
7.
Explain the quote “all life on Earth is fundamentally the same.”
In your OWN WORDS, explain the first law of thermodynamics.
In your OWN WORDS, explain the second law of thermodynamics.
What are the starting products for photosynthesis? What are the
end products?
What are the starting products for chemosynthesis? What are the
end products?
How is chemosynthesis different from photosynthesis?
Explain the general flow of energy through an ecosystem. (Where
does the energy start? In which form? Where does it go next? In
which form? Where does it end? In which form?)
13.3: Primary Productivity Is the Synthesis of
Organic Materials
• Oceanic primary
productivity: the
incorporation of carbon
atoms into carbohydrates
by photosynthesis or
chemosynthesis.
–Measured in grams of
carbon bound into
carbohydrates per square
meter of ocean surface
area per year gC/m2/yr.
13.3: How does primary productivity in
the oceans compare to life on land?
13.3: Global Primary Productivity
Oceanic productivity can be observed from space. NASA’s SeaWiFS
satellite, launched in 1997, can detect the amount of chlorophyll in ocean
surface water. Chlorophyll content allows an estimate of productivity. Red,
yellow, and green areas indicate high primary productivity; blue areas
indicate low. This image was derived from measurements made from
September 1997 through August 1998.
13.3: Food Webs Disperse Energy
through Communities
• What terms are used to describe feeding relationships?
• Autotrophs – “self-feeder” - organisms that make
their own food, also called producers.
• Heterotrophs – “other feeder” - organisms that
must consume other organisms for energy, also
called consumers.
13.3: Food Webs Disperse Energy
through Communities
• Trophic pyramid – a model that describes who eats whom
• Primary consumers/herbivores – these organisms eat
producers
• Secondary Consumers – these organisms eat primary
consumers, also known as carnivores
• Some may be ominvores
• Top consumers/carnivores – the top of the tropic pyramid
13.3: Trophic Pyramids
How many kilograms of primary
producers are necessary to
maintain 1 kilogram of tuna, a
top carnivore?
What is required for an average
tuna sandwich?
The quarter-pound tuna
sandwich has a long and
energetic history.
How much energy makes it to
the next trophic level? Why?
13.3: Food Webs Disperse Energy through
Communities
• Food web: group
of organisms linked
by complex feeding
relationships in
which the flow of
energy can be
followed from
primary producers
through consumers.
–Series of food
chains linked
together
–Arrows point to
the organism
that is getting
the energy.
13.4: Living Organisms Are Built From a Few
Elements
• Major components –
99% of mass of living
things (C, O, H, N)
• Marcronutrients –
other 1 %
• Atoms of these
combine to make
carbohydrates,
fats, proteins,
nucleic acids
(DNA)
• Micronutrients –
present in very small
quantities, but
necessary for life
The Carbon Cycle Is Earth’s
Largest Cycle
Carbon dioxide dissolved in
seawater is the source of
the carbon atoms
assembled into food
(initially glucose) by
photosynthesizers. When
this food is metabolized, the
carbon dioxide is returned
to the environment. Some
carbon dioxide enters the
atmosphere, some is
converted into bicarbonate
ions and becomes part of
marine organisms. When
these organisms die, their
shells decompose.
Nitrogen Must Be “Fixed” to Be
Available to Organisms
The Nitrogen Cycle.
The atmosphere’s vast reserve
of nitrogen cannot be
assimilated by living organisms
until it is “fixed” by bacteria and
cyanobacteria, usually in the
form of ammonium and nitrite
ions. Nitrogen is an essential
element in the construction of
proteins, nucleic acids, and a
few other critical biochemicals.
Upwelling and runoff from the
land bring useful nitrogen into
the photic zone, where
producers can incorporate it
into essential molecules.
Phosphorus and Silicon Cycle in
Three Distinct Loops
The Phosphorus Cycle.
Phosphorus is an essential
part of the energytransporting compounds
used by all of Earth’s lifeforms. Much of the
phosphorus-containing
materials in the ocean falls
to the seabed, is covered
with sediment, is subducted
by tectonic forces, and
millions of years later
returns to the surface
through volcanic eruptions.
13.3, 13.6 and 13.4 Concept Questions
1.
What do primary producers produce? How is this productivity
expressed?
2. Which areas of the ocean have the highest primary productivity?
3. Explain the three zones of the ocean based on light.
4. Compare and contrast heterotrophs and autotrophs.
5. Draw a trophic pyramid with 4 trophic levels. Label and define the
following parts – primary producer, primary consumer, secondary
consumer, and top conusmers.
6. Explain the three different types of consumers.
7. Compare and contrast a food web and a food chain.
8. Which elements make up about 99% of the mass of living things?
9. What are macronutrients? Give two examples.
10. What are micronutrients? Give one example.
13.7: Pollution in Food Webs
• Pollutants in food webs
works the OPPOSITE of
energy.
– As pollutants travel up the
food web, the concentration
gets larger and larger.
• Biomagnification:
accumulation of pollutants
at successive levels of the
food chain.
13.7: Pollution in Food Webs
• Biomagnification has
alarming consequences
for organisms at the top
of the food chain.
– Tertiary consumers and
top predators are
impacted the most
– This one reason why
U.S. states limit the
amount of fish people
can eat from certain
bodies of water.
• Mercury, DDT, other
pesticides, and fertilizers
13.7: Pollution in Food Webs
• Example:
DDT
caused
endange
rment of
brown
pelicans,
ospreys
& bald
eagle
13.7 Concept Questions
1. Explain the concept of biomagnification.
2. Which organisms are at most risk?
3. Give at least 2 examples of organisms
that have been impacted.
4. Should humans be concerned? Why?
13.6: Zones based on Light
Most of the biological
productivity of the ocean
occurs in an area near the
surface called the euphotic
zone (“good light”)
Below the euphotic zone
lies the disphotic zone
(“bad light”) where there
is light, but not enough for
photosynthesis to occur.
Below the disphotic zone
lies the dark aphotic zone
(“no light”), the vast bulk
of the ocean where sunlight
never reaches.
Zones based on depth
• Littoral zone- the part of
the coast which experiences low and high
tides.
• Pelagic (water) zone, it
is divided into 2 zones.
• Nearitic zone- from low
tide to the cont. shelf
• Oceanic zone- ocean
beyond the cont. shelf.
Zones based on the bottom
• Benthic zones describe the
ocean bottom
• Littoral zone- area covered
by high and low tides
• Sublittoral zone- continues
up to the continental shelf
• Bathyal zone- the area of
the continental slope.
• Abyssal zone- the area just
after the continental slope
• Hadal zone- the deepest
parts of the ocean, (trenches)
13.8: Evolution Appears to Operate by Natural Selection
• Evolution occurs through the process of natural
selection.
• The environment favors individuals that are well
adapted.
• Proposed by Darwin 1859
13.8: Evolution Appears to Operate by Natural Selection
• Steps of Natural Selection:
1. More offspring are produced than can survive.
2. Random variations (mutations) that are hereditary
get passed on to offspring.
3. Inherited trait is favorable (adaptations) and
increases chances of survival.
4. Those that survive reproduce and the favorable
trait accumulates in the population.
5. The environment does the selection. If the
environment changes, other traits may become
favorable.
1. What is the inherited trait?
2. What is the adaptation?
3. How does the population change over time?
13.8: Evolution “Fine Tunes” Organisms to Their
Environment
• Convergent evolution: the evolution of similar
characteristics in organisms of different ancestry
– Example: body shape (streamlining) in a shark,
ichthyosaur, penguin, dolphin.
13.8 Concept Questions
1. What is natural selection?
2. Explain how natural selection is different from evolution?
3. In your own words, explain how evolution by natural
selection operates. (1 point for each of the 5 steps.)
4. What is a mutation? How does it play a role in natural
selection?
5. What is an adaptation? How does it play a role in natural
selection?
6. What is convergent evolution?
13.9: Systems of Classification May Be
Artificial or Natural
• Taxonomy: the study of biological classification
• Classify by categories that can be universally
understood
• Artificial System of Classification: based on exterior
similarities, not ancestry or origin
• Lead to inaccuracies or false representations
• Natural System of Classification: based on
evolutionary history and developmental characteristics
• Common underlying natural origin
13.9: Systems of Classification May Be
Artificial or Natural
• Linnaeus: one of the first
persons to classify groups by
natural categories
• He developed a classification
system based on hierarchy –
grouping objects by degrees
of complexity
• He developed a system of
scientific names for
organisms
Classification Taxa
• There are seven main taxa into which organisms are classified; from the
general to specific:
1. Kingdom
(King)
Broad
2. Phylum
(Phillip)
3. Class
(Came)
4. Order
(Over)
5. Family
(For)
6. Genus
(Gold)
7. Species
(Specks)
Specific
• Example: The address of where you live.
– Kingdom =
– Phylum =
– Class =
– Order =
– Family =
– Genus =
– Species =
Classification Taxa: Scientific Name
• An organism’s scientific name represents two taxa:
– 1. Genus – is the taxon above species.
• Genus grouped species are considered to be closely related, i.e.,
there are 34 species of reef shark belonging to genus Carcharhinus.
– 2. Species – is the most specific of the taxa.
• Species is usually considered to be a group of organisms that can
reproduce together.
• Species are identified by referring to both the genus and the species, with
the genus capitalized and the species name in lower case.
Taxonomic Examples: Sea turtles!
Loggerhead
Green turtle
Leatherback
Kingdom
Animalia
Animalia
Animalia
Phylum
Chordata
Chordata
Chordata
Class
Reptilia
Reptilia
Reptilia
Order
Testiduines
Testiduines
Testiduines
Family
Cheloniidae
Cheloniidae
Dermochelyidae
Genus
Caretta
Chelonia
Dermochelys
Species
caretta
mydas
coriacea
13.9 Concept Questions – Day #1
1. In your own words, explain taxonomy.
2. How is the natural system of classification different
from an artificial system?
3. What were the significant contributions of
Linnaeus?
4. List, in order, the seven main classification
categories. Explain how the system is organized.
5. Explain an organisms scientific name. How do you
correctly indicate/write a scientific name?
13.9: Classifying Using a Dichotomous Key
• System of determining an organism’s classification by
answering questions that describe the organism.
– Simple “yes” or “no” questions to determine the scientific name
• Dicotomy = “two opposite parts or categories”
– Two opposing descriptions of basic features
Example
13.9: Three-Domain and Six-Kingdom System
3-Domain System: Based on the
types of cells
• Prokaryotes: single-celled
organisms without nuclei or
organelles.
1.Domain: Archaea (“old”)
2.Domain: Bacteria
• Eukaryotes: Cells having nuclei
and organelles
3.Domain: Eukarya
Cell Types
• Prokaryotes: structurally simple
– No complex internal membrane
structure.
– Lack chromosomes or a nucleus.
– Free-floating DNA or RNA.
– Lack mitochondria and chloroplasts.
– Believed to be the oldest types of
organisms – where the process of
photosynthesis began.
• Eukaryotes: complex cells.
– Kingdom Protista, Fungi, Plantae,
and Animalia are all eukaryotes
Six - Kingdom System and Three - Domain System
• The six-kingdom system:
1. Archaebacteria (Archae)
2. Eubacteria (Bacteria)
3. Protista (Eukarya)
4. Fungi (Eukarya)
5. Plantae (Eukarya)
6. Animalia (Eukarya)
Domain: Archaea
• Domain Archaea
– Kingdom Archaebacteria
– Proposed to be oldest living organisms
– Extremophiles – living in environments that
are inhospitable to most life.
• Thermophiles
• Methanogens
Domain: Bacteria
• Domain: Bacteria
– Kingdom: Eubacteria
– All other bacteria – common,
everyday bacteria
– Certain species can create
organic nitrogen
compounds by fixing
inorganic nitrogen from the air
– an essential element of life.
Domain: Bacteria
• The most important bacteria are in the phylum Cyanophyta (also known
as blue-green bacteria, blue-green “algae”, or cyanobacteria). Scientists
think that these bacteria are crucial to life because:
– Photosynthesis evolved in the cyanophytes.
– Cyanophytes were the primary organisms that
created the oxygen in the atmosphere.
– They are the only bacteria considered to be an
“algae.”
– Can be red – these pigments contribute to pink
color of African flamingos feeding on
red cyanophytes.
Cyanophyta – Blue-green Algae
550
Domain: Eukarya
• Domain: Eukarya
– Kingdoms: Protista, Fungi, Plantae, and Animalia
– Each cell has a nucleus
– Cells are typically larger than other 2 domains
– Most are multicellular organisms (some singlecelled)
13.9: The Kingdoms of Life
Bacteria
• Bacteria are extremely small, single-celled
organisms that usually have a cell wall and
reproduce by cell division.
• Unlike all other organisms, bacteria lack
nuclei.
• There are two main kinds of bacteria:
– Archaebacteria
– Eubacteria
Kingdom: Archaebacteria
• Bacteria that is only found
in extreme environmental
conditions.
• Examples:
1. Methangoens: live in
swamps and produce
methane gas.
2. Thermophiles: live in hot
springs and hydrothermal
vents.
3. Halophiles: live in
extremely salty conditions
Kingdom: Eubacteria
•
•
Most common bacteria – found in
everyday situations
Examples:
1. Decomposers - Break down
the remains and wastes
return the nutrients to the soil.
2. Others recycle nutrients, such
as nitrogen and phosphorus.
3. Cyanobacteria (blue-green
“algae”) – first
photosynthesizers.
4. Escherichia coli or E. coli,
is found in the intestines of
humans and other animals
and helps digest food and
release vitamins that humans
need.
Kingdom: Fungi
• A fungus is an organism whose cells have
nuclei, rigid cell walls, and no chlorophyll.
• Cell walls act like mini-skeletons that allow
fungi to stand up right.
• A mushroom is the reproductive structure of a
fungus. The rest of the fungus is an
underground network of fibers that absorb
food from decaying organisms in the soil.
Kingdom: Fungi
• Fungi get their
food by releasing
chemicals that
help break down
organic matter,
and then
absorbing the
nutrients.
• Like bacteria,
fungi play an
important role in
breaking down
the bodies of
dead organisms.
Kingdom: Fungi
• Examples:
1. Some fungi, like some bacteria, cause disease.
Athlete’s foot is an example of a condition
caused by fungi.
2. Other fungi add flavor to food as in blue
cheese. The fungus gives the cheese both its
blue color and strong flavor.
3. Yeasts are fungi that produce the gas that
makes bread rise.
Kingdom: Protists
•
•
Protists are diverse organisms.
Characteristics:
1. Some, like amoebas, are animallike. Others are plantlike,
such as kelp, and some resemble fungi.
2. Most protists are one-celled microscopic organisms,
which float on the ocean surface.
– Example: diatom
Protists
•
Examples:
1. From an environmental
standpoint, the most
important protists are
algae.
• Algae are plantlike
protists that can make
their own food using
the energy from the
sun.
2. Another protist,
Plasmodium, is the onecelled organism that
causes the disease
malaria.
Kingdom: Plants
• Plants are many-celled organisms
• Have cell walls.
• Make their own food using the
sun’s energy.
– Use their leaves to get sunlight,
oxygen, and carbon dioxide
from the air.
– Absorbing nutrients and water
from the soil using their roots.
• Leaves and roots are connected
by vascular tissue, which has thick
cell walls and serves is system of
tubes that carries water and food.
Kingdom: Animals
• Animals cannot
make their own
food. They must
take it in from the
environment.
• Animal cells also
have no cell walls,
making their bodies
soft and flexible.
Invertebrates
• Invertebrates are
animals that do not
have backbones.
Vertebrates
• Vertebrates are animals that have a
backbone
– includes mammals, birds, reptiles,
amphibians, and fish.
Kingdoms “Quiz”
1. Only thing on your desk should be scissors, glue, and a sheet
of blank paper.
2. You may not use your notes or anyone sitting around you.
3. Cut out the squares and match them up with the correct
kingdom.
4. Once you have everything matched, paste them onto your
sheet of paper.
5. Each kingdom has six corresponding boxes.
6. You have a limit of three questions to ask Ms. Watters (yes, I
am keeping track!)
7. You must show Ms. Watters your final product before you
leave for a grade.
8. After you get your grade, take this home and study it for your
quiz tomorrow.