Marine test 1

Question 1

Ecology

Answer 1

Ecology is the natural science of the relationships among living organisms, including humans, and their physical environment.

Question 2

Ecosystem

Answer 2

An ecosystem is a group of living (biotic) and nonliving (abiotic) things that interact with one another in a particular habitat

Question 3

Habitat

Answer 3

A habitat is an area in which a particular group of organisms live. Terrestrial (land), Aquatic (freshwater), Marine (saltwater)

Question 4

Aquatic

Answer 4

An aquatic animal is any animal, whether vertebrate or invertebrate, that lives in water for all or most of its lifetime.

Question 5

Marine

Answer 5

Marine biology is the scientific study of the biology of marine life, organisms in the sea.

Question 6

Abiotic factors

Answer 6

Abiotic factors in aquatic ecosystems refer to any non-living component of an ecosystem. Some examples of abiotic factors in aquatic ecosystems include light, salinity, oxygen content, rate of water flow, depth, temperature, and acidity.

Question 7

Biotic

Answer 7

Biotic factors of a marine ecosystem typically include algae, plankton, bacteria, seaweed, corals, fish, sharks, seals, whales, penguins and jellyfish.

Question 8

producer

Answer 8

These are organisms that can produce their own food. Plants are the prime example as they produce food via photosynthesis from sunlight.

Question 9

Consumer

Answer 9

These are organisms which eat other living organisms, rather than make their own food. The organisms that eats the producer is known as the
first order consumer. The organism that eats the first order consumer is known as the second order consumer.

Question 10

Decomposers

Answer 10

Decomposers are important to break down any dead plant and animal matter. Examples of decomposers are bacteria and fungi. Decomposers help maintain a cycle of energy flow within the ecosystem.

Question 11

Explain the difference between a pyramid of numbers & pyramid of biomass

Answer 11

Pyramids of numbers are a quantitative way of representing food chains. They record the number of organisms at each trophic level in a food chain. A pyramid of biomass is a graphical portrayal of biomass present in a unit of the territory of different trophic levels.

Question 12

Types of coral reefs

Answer 12

1. Fringing reef- form around a land mass reefs off beaches on continent islands.
2. Barrier reef- parallel to the shore but is separated by a channel of water.
3. Atoll reef- a ring shaped coral reef that surrounds a lagoon, mainly found in pacific regions.

Question 13

Hard corals characteristics

Answer 13

• Tentacles in multiples of 6 (subclass hexacorallia)
• Created limestone skeleton.
• Majority are reef builders.
• Both colonial and solitary
• Bleach when stress.
• Skeleton remains after death

Question 14

Soft corals

Answer 14

• Tentacles in multiples of 8 (subclass octocorals
• No limestone skeleton
• Non-reef builders
• Both colonial and solitary
• Bleach when stressed
• No trace after death

Question 15

Coal reef structure

Answer 15

• Corals are invertebrates and belong to Phylum Cnidaria
• Majority live in colonies where thousands of polyps live together and share nutrients.
• Polyps sit in cavities in the skeleton.

Question 16

Anatomy and energy gain

Answer 16

• Corals have a symbiotic relationship with plant like algae called zooxanthelle
• Day time: zoox, photosynthesises passing sugars to the coral.
• Night time: coral uses tentacles which have stinging cells (nematocyst) to capture prey (plankton)

Question 17

What is a mangrove

Answer 17

A mangrove is a shrub or tree that grows mainly in coastal saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines and tidal rivers. Mangroves occur naturally in most coastal areas of Western Australia from Shark Bay northwards.

Question 18

Describes threats to mangroves environments

Answer 18

Greater pressure is placed on the mangrove environment from both direct and indirect sources such as dumping of waste, trampling by humans, climate change and sea level rise and many other factors.

Question 19

Describes the adaptations of mangroves

Answer 19

They have developed particular ways of dealing with concentrations of salt that would kill or inhibit the growth of most other plants as they experience large fluctuations in salinity: being inundated by seawater (high salinity) during high tides, while at low tide, or during heavy rains or floods, they can be exposed to open air or fresh water (low salinity).

Question 20

Explains how mangroves are useful/important

Answer 20

They are also the popular home and habitat and hiding location from prey for of the estuarine crocodile, as well as birds, snakes and mollusks.

Question 21

Explain what seagrass is

Answer 21

Seagrass belong to group called monocotyledons (grasses, lilies, palms).
Seagrass have roots, rhizomes, veins, leaves, flowers and seeds.

Question 22

Describes the locations where seagrass is found

Answer 22

Seagrasses are found in shallow salty and brackish waters in protected coastlines. Depends on light for photosynthesis. Shallow depths 1-3 meters.

Question 23

Describes conditions seagrass needs to grow

Answer 23

Depend on light for photosynthesis. Shallow depths 1 to 3 meters, but the deepest growing seagrass (Halophila decipiens) has been found at depths of 58 meters. Can form dense meadows, large enough to see from space.

Question 24

Describes the adaptations of seagrass

Answer 24

• Physical environment: produce oxygen, absorb excess nutrients, slow water flow, capture sand, dirt and silt particles. Roots stabilise sediment (improves water clarity and reduce coastal erosion).
• Habitat: nursery for juvenile fish, crustaceans, molluscs ect., protection for small organisms.
• Producer: foundation of coastal food webs, feeding grounds for thousands of species around the world (dugongs, turtles eat the blades)
• Blue carbon: absorbs CO2 from the atmosphere through photosynthesis.

Question 25

Describes threats to seagrass meadows

Answer 25

• Excess nutrients: causes bacteria to thrive releasing toxins. Increases phytoplankton causing less light received for photosynthesis.
• Dredging: increases sediment in water column = less light for photosynthesis.
• Physical damage: boats, anchors, chains and moorings, coastal development, storms, cyclones.
• Pollution from run off, oil etc.

Question 26

Explain what an estuary is

Answer 26

Tidal mouth of a large river, where the tide meets the stream. Partially enclosed costal body of water of brackish with one or more rivers/streams flowing into it and a connection to the sea. Estuaries are a transition zone between river and maritime environments and are impacted by both tides, waves, salt and fresh water.

Question 27

Types of estuaries

Answer 27

1. Drowned river valleys- coastal plain estuary, lagoon/bar built- separated by sand bars/sediment.
2. Fjord- eroded valleys formed by glaciers.
3. Tectonic produces- formed by plate movement.

Question 28

Describes water quality of estuaries

Answer 28

Estuaries based on water circulation.
- Stal wedge- more river output than marine, tide effect minimal, fresh floats on top of salt
- Partially mixed- tidal influence causes marine output to overtake river output, water becomes partially mixed.
- Well mixed- tidal influences causes marine output to overtake river output, no clear fresh and sea water boundary.
- Inverse- occurs in dry locations with high rates of evaporation and low rates of river input.
- Intermittent- estuary type varies a lot and can change from one to the other.

Question 29

Define osmoregulation

Answer 29

Osmoregulation is a physiological process that an organism used to maintain water balance, avoid excess water gain and maintain osmotic concentration of bodily fluids including salt content.

Question 30

why the Dawesville Cut (south of Mandurah) was built

Answer 30

The peel Harvey estuary was having issues- increased nutrients, algal blooms, rooting algae and lacking the ability to support fauna and flora. The channel allows the system to be flushed with ocean water.

Question 31

Quadrat Sampling

Answer 31

Is a portable frame used to mark a quadrant. It uses a series of set squares that are placed in habitats and the species inside the quadrant are identified and recorded. The recording can be performed by counting and or photographing for future analysis

Question 32

Transect Sampling

Answer 32

Transect lines are used by scientists to estimate the number of species, items ect in a certain area. A straight line is run along a set of distance

Question 33

Mark/capture/recapture

Answer 33

Particular species are caught by either nets traps ect are tagged or marked and then released back into the environment. Data such as length age weight and reproduction can be recorded

Question 34

Sled/Trawl/Bongo Nets

Answer 34

Species can be collected through varying nets, travels and sleds and biodiversity studies can be performed. Usually towed behind a boat for a set distance and species collected, counted and sorted for further research. Used to collect information about plankton

Question 35

Remote Sensing and Satellites

Answer 35

Used to see larger scale data of the ocean. Ocean temperatures, migration patterns, sea level rise, weather and depth can be measured using this technology. Electromagnetic radiation is sent to earth and the reflected radiation records data and then is available for interpretation.

Question 36

Remotely Operated Vehicles

Answer 36

An underwater robot that can be used to explore the deep ocean. Has robotic arms, lights and cameras that are able to record data at varying depths?

Question 37

BRUV Sampling

Answer 37

Baited remote underwater video sampling. Allows scientists to access areas without being there although it impacts animals’ behavior due to the bait. Baited Remote Underwater Video Station (BRUV’s) - Ocean First Institute

Question 38

Manta Tow Surveys

Answer 38

Used to provide a general description of large areas of reef and to gauge broad changes in abundance and distribution of organisms on coral reefs. The observer holds on to the Manter board attached to the boat by a length of rope. Then makes a visual assessment of specific variables during each timed manta tow

Question 39

Apex predators

Answer 39

A predator that exists at the very top of the food chain. Unlike some other predators, it’s never preyed upon itself.