Presentation on theme: "Chapter 13 Life in the Ocean Oceanography An Invitation to Marine Science, 7th Tom Garrison."— Presentation transcript:
Chapter 13 Life in the Ocean Oceanography An Invitation to Marine Science, 7th Tom Garrison
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
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). 13.2: Energy Can Be Stored through Photosynthesis
Fig. 13-3, p. 347 Stepped Art Sun Light energy Producers Photosynthesizers: Green plants and algae, and specialized bacteria Chemical energy (carbohydrates, etc.) Consumers Respirers: Animals and decomposers and plants at night Energy of movement, waste heat, entropy To space
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.Explain the quote “all life on Earth is fundamentally the same.” 2.In your OWN WORDS, explain the first law of thermodynamics. 3.In your OWN WORDS, explain the second law of thermodynamics. 4.What are the starting products for photosynthesis? What are the end products? 5.What are the starting products for chemosynthesis? What are the end products? 6.How is chemosynthesis different from photosynthesis? 7.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/m 2 /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
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: Trophic Pyramids
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. 13.3: Food Webs Disperse Energy through Communities
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 energy- transporting compounds used by all of Earth’s life- forms. 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 exper- iences 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.
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
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 13.9: Three-Domain and Six-Kingdom System
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 –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.
5 - 50 Cyanophyta – Blue-green Algae
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 single- celled)
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 one- celled 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.