AICE Marine Science Chapter 4 Vocab (New Coursebook)

Ocean

A continuous mass of seawater on the Earth's surface, its boundaries formed by continental land masses, ridges on the ocean floor, or the equator

Seas

Smaller and less deep bodies of seawater that are partially enclosed by land; they are found where the ocean and land meet

Taxonomic Hierarchy

The classification of the species within living organisms by describing the domain, kingdom, phylum, class, order, family, genus, and species

Binomial Nomenclature

The two-part Latin name given to each species comprising the genus followed by the species

Dichotomous Key

An identification tool utilising a series of choices between alternative characters, with a direction to another stage in the key, until the species is identified

Biological Drawing

A scientific drawing that records an image and important features of the specimen

Plankton

Microscopic free floating marine organisms

Phytoplankton

Microscopic photosynthetic organisms that live in the upper, sunlit layers of water

Zooplankton

Planktonic consumers that are either floating or weakly swimming animals

Echinoderms

A marine invertebrate group with pentaradial symmetry and tube feet

Crustaceans

A marine invertebrate group with a hard exoskeleton, ten jointed legs, and a nauplius larvae stage

Bony Fish

Fish that have a bony skeleton and belong to the class Osteichthyes

Cartilaginous Fish

Fish that have jaws and skeletons made only of cartilage and belong to the class Chondrichthyes

Macroalgae

Marine producers such as kelp and seaweed

Marine Grasses

Aquatic flowering plants that are often found in estuarine and coastal environments

Keystone Species

An organism that plays a unique and crucial role in the way an ecosystem functions; without them, the ecosystem would be dramatically different or cease to exist altogether

Larvae

A planktonic stage of development which occur between egg and juveniles; found in nearly all species of fish and invertebrates

Pentaradial Symmetry

Five arms (or fans) radiating from a central body cavity

Tube feet

Tubular projections that assist in locomotion, feeding, and respiration

Nauplius

Distinctive larval stage of crustaceans

Carapace

The part of the exoskeleton that protects the dorsal side of the cephalothorax

Gills

The gaseous exchange surface of fish

Operculum

A thin bony flap of skin covering and protecting the gills

Lateral Line

A canal on the head and the side of the fish that contains sense organs; it is externally visible in bony fish but in cartilaginous fish it is under the skin

Scales

Overlapping segments of bone covered by skin and mucus found on the outside of the fish

Fins

Protrude from the body surface and assist in movement, stabilising position, reproduction, and protection

Swim Bladder

A buoyancy organ found in bony fish

Denticles

A type of overlapping scales that provide protection and improved hydrodynamic efficiency in sharks

Gill slits

External opening from the gills through which water taken in at the mouth can pass back to the ocean

Features of Chordates

Notochord, dorsal neural tube, pharyngeal slits, and post-anal tail

Holdfast

Strong, root-like structure that anchors the macroalgae to the seabed

Stipe

Long, tough, vertical stalk similar to the stem of plants

Blades

Leaf-like structures that 'hang' in the water and absorb light and minerals

Gas Bladder

A gas-containing structure that provides buoyancy for some species of seaweed

Root

Structure at the based of a plant that anchors it to the substrate and absorbs nutrients from the sediment

Rhizomes

A horizontal underground structure that enables seagrasses to reproduce asexually

Leaf

Photosynthetic organ of plants

Flower

Sexual reproductive organ of plants

Biodiversity

A measure of the species, genetic, and ecosystem diversity of different species

Species Diversity

The abundance and richness of a species in a given place

Genetic Diversity

The variety of forms of genes (alleles) within a species

Ecological Diversity

The variation of ecosystems or habitats on a regional or global level

Ecosystem

The living organisms and the environment with which they interact

Habitat

The natural environment where an organism lives

Niche

The role of a species within an ecosystem

Species

A group of similar organisms that can interbreed naturally to produce fertile offspring

Population

All the individuals of the same species that live at the same place and time

Community

All the different populations interacting in one habitat at the same time

Biotic Factors

The living parts of an ecosystem, which includes the organisms and their effects on each other

Disease

An illness characterised by specific signs and symptoms

Intra-specific Competition

Competition between individuals of the same species (for example, for food or a mate)

Inter-specific Competition

Competition between members of different species (for example, predator-prey)

Abiotic Factors

The environment's geological, physical, and chemical features; the nonliving part of an ecosystem

Mark-Release-Recapture

A method to estimate the population size of a mobile species

Lincoln Index

A mathematical equation that can use the mark-release-recapture data to estimate the population size

Frame Quadrat

A plastic or metal square that sets a standard unit of area for study of the distribution of marine organisms

Transect

A rope or tape marked at regular intervals that sets standard distances for study of the distribution of marine organisms

Line Transect

A sampling method involving counting of species that touch the transect

Continuous Sampling

Samples are taken along the whole length of the transect

Systematic Sampling

Samples are taken at fixed intervals along the transect

Belt Transect

A sampling method involving counting of species in frame quadrats placed adjacent to the transect

Random Sampling

Samples are taken at random places within the sample site

Ethical Method

Evaluates and chooses ways to protect the natural habitat under investigation

Safe Method

Identifies potential hazards and then reduces their risk of occurring

Kite Graph

A graph of the distribution and abundance of organisms in the littoral zone that allows zonation patterns to be easily seen

Richness

The number of species in a community

Evenness

A measure of the relative abundance of the populations of different species in an area

Simpson's Index of Diversity (D)

A biodiversity measure that accounts for both species richness and evenness

Null Hypothesis (H0)

There is no correlation between the two sets of variables

Hypothesis

An explanation of an observation that can be tested through experimentation

Scatter Graph

When two sets of variables are plotted to indicate if there is a relationship between them

Spearman's Rank Correlation

A mathematical tool used to find out if there is a correlation between two sets of variables, when they are not normally distributed

Critical Values of rs

Indicate when the calculated Spearman's rank is sufficient to suggest a correlation between the two sets of variables

Alternative Hypothesis

There is a significant correlation between two sets of variables