Chapter 4: The Biology of Life.
Ch 4, 5, 6 TEST Thursday, Oct. 24th
8 Characteristics of Life
Photosynthesis
Bold words, know definitions
Who does it?
What it is?
Materials Needed?
Respiration
Who does it?
What is it?
Materials Needed?
Aerobic vs. Anaerobic
Autotrophs and Heterotrophs
Prokaryotes vs. Eukaryotes cells/organisms
Prokatyotes:
 Primitive cells
 Ancient, simple, small
 No membrane-bound organelles
 Ex: Bacteria, Archaea
 Prokaryotes have few structures:
 Cell wall – support
 Ribosomes – assemble proteins
 DNA – loose in the cytoplasm
 Flagella – locomotion
Eukaryotic cells are organized and complex
 Larger than prokaryotes
 Membrane-bound organelles
 Have specialized organelles
 DNA contained in a nucleus.
The vast diversity of organisms in the ocean came through millions of years of evolution
= The gradual alteration of a species’ genetic makeup
= Explains how species change over time
Evolution occurs because of genetic differences
Individual organisms show variation in how they:
 Find food, avoid being eaten, reproduce, find mates, metabolize, etc.
 The best-adapted for the above activities 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.
Classifying Living Things
Species =
Binomial Nomenclature. Universal, Latin, Genus species, Italics Ex: Macrocystis pyrifera
Organisms are grouped according to their relatedness
 Related organisms share an evolutionary history, or phylogeny
 Share a common ancestor
 What do scientists look at to determine common ancestor?
3 Domains and characteristics of each
1) Domain Bacteria
Has 1 kingdom – the Eubacteria
2) Domain Archaea
Prokaryotes
Contains 1 kingdom – the Archaebacteria
3) Domain Eukarya
Includes all kingdoms composed of organisms made up of eukaryotic cells
– 4 Kingdoms: Protista, Fungi , Animalia , Plantae
Taxonomy = the study of classification and naming living organisms
Each grouping is called a Taxon, Taxa plural
Kingdoms are divided into groups called phyla
Phyla are subdivided into classes
Classes are subdivided into orders
Orders are subdivided into families
Families are divided into genera
Genus contain closely related species
Species are unique
Chapter 5: Microbial World
Prokaryotes: “Before nucleus”
 2 Domains, 2 Kingdoms:
 Bacteria and Archaea (more closely related to Eukaryotes)
 Simplest and oldest life forms
 Cell wall, cell membranes
 No membrane bound organelles
 DNA not in a nucleus
 Great metabolic diversity
Domain Bacteria
Most abundant form of life on earth!
Ecosystems Importance:
 Break down organic material into nutrients for other organisms to use
 Cause diseases in marine animals
 Phytoplankton blooms
Impact on humans:
 Disease in humans
Eukaryotes
 Food spoilage
 Respiratory issues, rash.
 Toxins stored in shellfish, then humans eat it.
Other significance of Bacteria
 Symbiotic Bacteria = associates with other organisms closely.
 Parasites-harmful
 Beneficial, Live in a host organism
 Examples of Beneficial
 Wood-Digesting Bacteria in wood eating organisms
 Bioluminescence: attract mates, lure prey, communicate
 Examples of Parasitic
 Some toxic
Ex of Bacteria: Cyanobacteria
 Photosynthetic
 Most abundant photosythetic org. in ocean
CYANOBACTERIA and RED TIDE
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Unpredictable, unsure of cause.
Massive blooms of phytoplankton
 Some toxic
 By cyanobacteria, dinoflagelletes, diatoms
 Harms marine life:
-cuts fish gills, deplete oxygen levels, some poisonous
 Harms humans
-toxic fumes cause sore throats, respiratory issues, eating marine life that stores these toxins-harmful/deadly
Domain Archaea
 Ancient organisms – fossils found that date back 3.8 billion years
 Extremophiles – Found in extreme environments like hydrothermal vents and salt flats (two
very extreme environments)
 Variety of metabolic types
 Widely distributed in the marine community-not all Extremophiles
 They can tolerate wide ranges in temperature, salinity and even desiccation (drying out)
NOW ENTERING DOMAIN EUKARYA…
Unicellular Algae
 Eukaryotes-Protists (some animal-like/some plant-like)
 Membrane bound organelles = “little organs”
 Have a nucleus containing DNA
 Unicellular
 Cell Wall
 silicon in diatoms; cellulose in dinoflagellates
 Most photosynthetic
 Often animal-like
 Flagella
 Some heterotrophic
Diatoms
 Photosynthetic
 Shell of Silica
 Most important primary producer on Earth
 Oxygen And Bottom of the food chain
Dinoflagellates
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Two flagella in grooves on body for motion
Shell made of Cellulose
Some are bioluminescent, produce light
Sometimes cause Red Tide
*Zooxanthelle and their relationship with corals.
*Ecosystem Significance of Unicellular Algae, Impacts on Humans
Protozoans= “First animals”
 Animal-like
 Single cell
 Heterotrophs, ingest food (Some photosynthetic)
 Found everywhere in oceans
 3 main types:
 Foramaniferans
 Radiolarians
 Ciliates
 Ecosystem Significance of Protozoans/Impact on Humans
Chapter 6: Multicellular Producers
Multicellular Algae =Seaweeds
 Eukaryotic
 Primary producers
 Not weeds, but algae.
 Most biologists agree that macrophyte is a much better name, macroalgae too.
 Lack true leaves, stems, and roots
Physical Characteristics:
 Thallus = the complete body
 Blade = leaf like, flattened portions
 Pneumatocysts = gas filled bladders, keep upright so towards sunlight
 Stipe = stem-like
 Holdfast = attaches seaweed to a substrate
Types of Macroalgae
1) Chlorophyta = Green
 Have the same pigments as land plants (chlorophyll)
 More than 7,000 species
2) Phaeophyta = Brown
 Largest (size) and most complex of the algae
 Kelps are the largest seaweed we encounter in the ocean. They are also the most complex.
 Due to this large size, many of the kelps are harvested for food!
Example: Giant Brown Kelp, Macrocystis pyrifera
-The largest of the kelps.
-anchors itself to the sea floor by use a massive holdfast.
-extensive pneumatocysts used for buoyancy.
-Pneumatocysts keep the seaweed close to the surface to maximize photosynthesis
3) Rhodophyta = Red
Most in Marine habitats, 4,000 species.
-Substances we get from algae: Algin and carageenan
-Know some products made from algae
Flowering Plants:
 Flower, reproductive organ
 Photosynthetic
 Eukaryotes
 True stems, roots, leaves
 Dominant on Land, few Marine species
 True Flowering Plants: Seagrasses
 Salt Tolerant Plants:
 Salt Marsh grasses
 Mangroves
Seagrasses:
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Seagrasses have rhizomes, or horizontal stems which grow beneath the sediments
Provides habitat for juveniles and larvae of many marine species
Anchors sediments
Importance of:
Helps stabilize soft bottoms
Protects coast from turbulence and erosion
Salt Marsh Plants:
 Salt water tolerant species = halophytes
 Do not tolerate total submergence
 Act as water purification system
 Habitat and breeding grounds for many fishery species
 Protect against erosion
Mangroves:
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Trap and cycle organics, chemical elements, sediment and minerals.
Leaf litter important for decomposition, recycling nutrients.
Shelter/habitat for marine organisms—often economically important ones.
Nearly all commercially/recreationally important fisheries spend a portion of life in mangroves
and/or seagrass
Stabilize the coastline, reducing erosion from storm surges, currents, waves, and tides.
PLANKTON: “drifters, wanderers”
Zooplankton (animal-like, Heterotrophs, eat each other and Phyto. ) vs. Phytoplankton (plant-like, autotrophs)
Multiple Choice
True-False
Matching
Short Answer/Free Response
Ecosystems Significance of Bacteria, Protozoans, Unicellular Algae
Ecosystem benefits of Seagrass and Mangroves
Euk and Prok differences
Autotrophs vs. Heterotrophs
List the 7 Taxa
Label parts of Seaweed
List the 3 types of Protozoans
List 3 Domain
How are species classified?
Define any of the bold faced words