Marine Bio Unit 1 Study Guide
Marine Biology
Unit 1 Test Study Guide
Topics to Know:
What is marine biology?
Marine biology is the study of living organisms in the ocean (plants, animals, microbes) and focuses on the behaviour, sociology, genetics, ecology, and marine life.
How much of the earth is made up of water
70% of the earth is made up of water.
How to locate the 5 oceans AND the 7 continents on a map
The 8 categories of scientific classification and which is most broad and which is most specific
Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species
The names of the 3 domains and 6 kingdoms
3 domains = Bacteria, Archaea, and Eukarya
6 kingdoms = Bacteria, Archaea, Protista, Fungi, Plantae, and Animalia
How to write a scientific name for an organism
The name consists of 2 parts, the first name is the genus and the second name is the species.
What evolution is and how it occurs. Summarize Darwin’s Theory of Evolution
Evolution is the change in genetics over generations, and occurs via natural selection. Darwin’s Theory of Evolution by Natural Selection says that organisms with better traits or traits with more advantage are more likely to survive, which causes these traits to become more common over time.
The struggle for existence and survival of the fittest
The struggle for existence is when an organism struggles to survive because of competition regarding food and water. The survival of the fittest is the result, meaning that organisms with better traits are more likely to survive.
Descent
Traits of that are passed down to generations, and the better the trait the more likely it is to be passed down.
Evidence for evolution
The fossil records of organisms changing over time and the competitive anatomy meaning that different species have had similar structures and indicate a common ancestor.
The reasons why humans evolved to have many skin colors
Humans have evolved many skin colors because of ultraviolet radiation (UV). Darker skin tones developed in Africa, which is closer to the equator and where UV radiation is most intense. Its function is to provide protection against strong UV rays, helping to reduce the risk of skin cancer. Lighter skin tones developed in populations that migrated away from the equator to the north with less sunlight. Its function is to absorb UV rays more easily, allowing the body to produce vitamin D.
Trophic levels and how energy is transferred through them
Trophic levels are basically steps/levels in the food chain. First is the Producers (autotrophs:make their own food) like plants and algae, making their own food using photosynthesis. Next is Primary Consumers (herbivores: essentially vegans), animals that eat producers like rabbits and caterpillars. Secondary Consumers (carnivores/omnivores) animals that eat primary producers like snakes and frogs. Then comes tertiary consumers, which eat secondary consumers. Lastly are Quaternary consumers (Apex predators), basically top predators that have no threats like lions and orcas.
Energy enters the ecosystem via producers (from sunlight), and what happens is that energy moves up each trophic level when one organism eats another. But, only 10% of energy is passed on to the next level, the rest is lost to heat, movement, growth or waste. (10% rule).
Why primary producers are important
They're important because they're the base of the food chain, and convert external energy to energy that is actually usable for other organisms.
The four main marine primary producers
Phytoplankton, seaweeds (kelp), seagrass, and microalgae.
The difference between phytoplankton and zooplankton and how to identify them based on their body structure.
Phytoplankton are tiny plant-like organisms that produce their own food through photosynthesis (Primary Producers) and are autotrophs. They are usually unicellular, and often have a green or brown tint due to chlorophyll. They often live in the upper sunlit layer of the water. A few examples are diatoms, cyanobaceria, dinoflagellates, and green algae.
Zooplankton are tiny animal-like organisms that cannot produce their own food (Primary or Secondary Consumers) and are heterotrophs. They feed on phytoplankton or other zooplankton. Zooplankton can be unicellular, like protozoa, or multicellular, like tiny crustaceans. They often live in the upper sunlit layer of the water. Examples include copepods, krill, salp, jellyfish larvae, and amphipods.
Phytoplankton have chloroplasts and sometimes flagella for movement; zooplankton often have antennae or transparent bodies for floating and hiding.
If phytoplankton in an area died, the entire marine food chain would collapse because zooplankton and other consumers would lose their main food source. This would lead to less oxygen production (since phytoplankton make most of Earth’s oxygen), massive marine die-offs, and negative impacts on humans who rely on seafood and healthy oceans.
Vocabulary to Know:
Marine biology – the study of organisms that live in the ocean
Oceanography – the scientific study of oceans, including physical, chemical, and biological aspects.
Domain, kingdom, phylum, class, order, genus, species – the hierarchical system used to classify living things.
Eukarya, Bacteria, Archaea – the three domains of life; Eukarya have nuclei, Bacteria and Archaea are single-celled without nuclei.
Evolution – the change in species over time.
Theory – a well-supported explanation for a natural phenomenon.
Natural variation – differences among individuals in a population.
Natural selection – the process where organisms with traits best suited to their environment survive and reproduce.
Artificial selection – humans selectively breeding organisms for desired traits.
Trophic pyramid – a diagram showing the flow of energy through trophic levels in an ecosystem.
Primary producers – organisms that make their own food, usually through photosynthesis.
Plankton – tiny organisms that drift in water and cannot swim against currents.
Zooplankton – animal-like plankton that feed on other plankton.
Phytoplankton – plant-like plankton that produce their own food through photosynthesis.
Holoplankton – plankton that spend their entire life cycle drifting in water.
Meroplankton – plankton that spend only part of their life cycle drifting, usually as larvae.