Marine Biology - Middle School

Dive into this list of marine biology terms and learn all about the creatures that live in the oceans and seas. You'll explore a fascinating underwater world that's home to algae, whales, coral reefs, and more. Just watch out for sharks!
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Full list of words from this list:

words only definitions & notes
  1. abyssal
    relating to ocean depths from 2000 to 5000 meters
  2. adaptation
    the process of adjusting or conforming to new conditions
  3. algae
    primitive chlorophyll-containing aquatic organisms
  4. anemone
    a marine polyp that resembles a flower
  5. aphotic
    lacking light; especially not reached by sunlight
  6. arthropod
    invertebrate having jointed limbs and a segmented body
  7. autotroph
    an organism capable of synthesizing its own food
  8. baleen
    a horny material from the upper jaws of certain whales
  9. barnacle
    marine crustacean with feathery food-catching appendages
  10. barrier reef
    a long coral reef near and parallel to the shore
  11. bathyal
    relating to ocean depths between 200 and 2000 meters
  12. benthic
    of or relating to or happening on the bottom under a body of water
  13. benthos
    a region including the bottom of the sea and the littoral zones
  14. biodiversity
    the variety of plant and animal life in a habitat
  15. bioluminescence
    luminescence produced by physiological processes
  16. biotic
    of or relating to living organisms
  17. bivalve
    a sea creature with two connected hinged shells
  18. blubber
    an insulating layer of fat under the skin of some animals
  19. bony fish
    any fish of the class Osteichthyes
  20. brown algae
    algae having the chlorophyll masked by brown and yellow pigments
  21. buoyancy
    the tendency to float in water or other liquid
  22. carnivore
    a terrestrial or aquatic flesh-eating mammal
  23. cartilage
    tough elastic tissue, mostly converted to bone in adults
  24. cartilaginous fish
    fishes in which the skeleton may be calcified but not ossified
  25. caudal fin
    the tail of fishes and some other aquatic vertebrates
  26. cephalopod
    a marine animal with a head and tentacles
  27. chemosynthesis
    synthesis of carbohydrate from carbon dioxide and water
  28. cilium
    a hairlike projection from the surface of a cell
  29. cnidarian
    radially symmetrical animals having saclike bodies with only one opening and tentacles with stinging structures; they occur in polyp and medusa forms
  30. community
    group of interdependent organisms living in the same region
  31. coral
    a very small ocean creature that often forms reefs
  32. coral reef
    a reef consisting of coral consolidated into limestone
  33. crustacean
    mainly aquatic arthropod usually having a segmented body
  34. cuttlefish
    ten-armed oval-bodied cephalopod with narrow fins as long as the body and a large calcareous internal shell
  35. desalination
    the removal of salt
  36. diatom
    microscopic unicellular marine or freshwater colonial alga having cell walls impregnated with silica
  37. dinoflagellate
    chiefly marine protozoa having two flagella
  38. dorsal fin
    unpaired median fin on the backs of fishes and some other aquatic vertebrates that help to maintain balance
  39. echinoderm
    marine invertebrates with tube feet and five-part radially symmetrical bodies
  40. ecosystem
    organisms interacting with their physical environment
  41. effluent
    water mixed with waste matter
  42. endangered
    in imminent threat of extinction
  43. environment
    the area in which something exists or lives
  44. epilithic
    growing on stone
  45. estuary
    the wide part of a river where it nears the sea
  46. eutrophication
    nutrient saturation of water leading to oxygen depletion
  47. extinct
    no longer in existence
  48. fin
    organ of locomotion and balance in fishes and some other aquatic animals
  49. flagellum
    a lash-like appendage used for locomotion
  50. food chain
    community of organisms where each member is eaten by another
  51. food web
    community of organisms with several interrelated food chains
  52. gastropod
    a class of mollusks typically having a one-piece coiled shell and flattened muscular foot with a head bearing stalked eyes
  53. gill
    organ allowing aquatic animals to obtain oxygen from water
  54. green algae
    algae that are clear green in color
  55. habitat
    the type of environment in which an organism normally lives
  56. herbivore
    any animal that feeds chiefly on grass and other plants
  57. heterotroph
    an organism that cannot make its own food supply
  58. hydra
    small tubular solitary freshwater hydrozoan polyp
  59. intertidal
    of or relating to the littoral area above the low-tide mark
  60. invertebrate
    any animal lacking a backbone or notochord
  61. jellyfish
    a marine animal with a bulbous body and long tentacles
  62. kelp
    large brown seaweeds having fluted leathery fronds
  63. larva
    immature form of an animal between the egg and adult stages
  64. lateral line
    sense organs of fish and amphibians
  65. mammal
    a warm-blooded vertebrate having the skin covered with hair
  66. manatee
    sirenian mammal of tropical coastal waters of America
  67. mantle
    a protective layer of epidermis in mollusks or brachiopods
  68. medusa
    one of two forms that coelenterates take: it is the free-swimming sexual phase in the life cycle of a coelenterate; in this phase it has a gelatinous umbrella-shaped body and tentacles
  69. mollusk
    aquatic invertebrate, often with a shell
  70. motile
    capable of movement
  71. nekton
    the aggregate of actively swimming animals in a body of water ranging from microscopic organisms to whales
  72. neritic
    relating to the region of shallow water adjoining the seacoast
  73. niche
    status or place of an organism within its environment
  74. octopus
    bottom-living cephalopod having a soft oval body with eight long tentacles
  75. oviparous
    egg-laying
  76. pectoral fin
    either of a pair of fins situated just behind the head in fishes that help control the direction of movement
  77. pelagic
    relating to, occurring in, or living in the open ocean
  78. photic
    of or relating to or caused by light
  79. photosynthesis
    formation of compounds in plants aided by radiant energy
  80. phytoplankton
    photosynthetic or plant constituent of plankton
  81. plankton
    aggregate of small organisms that float or drift in water
  82. pollution
    contamination of the natural environment
  83. polyp
    one of two forms that coelenterates take (e.g. a hydra or coral): usually sedentary with a hollow cylindrical body usually with a ring of tentacles around the mouth
  84. predator
    any animal that lives by preying on other animals
  85. prey
    animal hunted or caught for food
  86. protozoan
    any of diverse minute acellular or unicellular organisms usually nonphotosynthetic
  87. radial symmetry
    the property of symmetry about an axis
  88. ray
    cartilaginous fishes having horizontally flattened bodies and enlarged winglike pectoral fins with gills on the underside; most swim by moving the pectoral fins
  89. red algae
    marine algae in which the chlorophyll is masked by a red or purplish pigment; source of agar and carrageenan
  90. red tide
    seawater that is discolored by large numbers of certain dinoflagellates that produce saxitoxin
  91. regeneration
    growth anew of lost tissue or destroyed parts or organs
  92. salinity
    the relative proportion of salt in a solution
  93. scale
    a rigid plate forming part of the body covering of animals
  94. seagrass
    any of various seaweeds that grow underwater in shallow beds
  95. seaweed
    plant growing in the sea, especially marine algae
  96. sessile
    attached directly by the base
  97. shark
    any of numerous elongate mostly marine carnivorous fishes with heterocercal caudal fins and tough skin covered with small toothlike scales
  98. species
    taxonomic group whose members can interbreed
  99. spine
    the series of vertebrae forming the backbone
  100. sponge
    primitive multicellular marine animal whose porous body is supported by a fibrous skeletal framework; usually occurs in sessile colonies
  101. squid
    widely distributed fast-moving ten-armed cephalopod mollusk having a long tapered body with triangular tail fins
  102. starfish
    a marine animal with five pointed arms
  103. stingray
    large venomous ray with large barbed spines near the base of a thin whiplike tail capable of inflicting severe wounds
  104. substrate
    a surface on which an organism grows or is attached
  105. swim bladder
    an air-filled sac near the spinal column in many fishes that helps maintain buoyancy
  106. symbiosis
    the relation between two interdependent species of organisms
  107. tentacle
    a flexible appendage adapted for grasping or feeling
  108. turtle
    any of various aquatic and land reptiles having a bony shell and flipper-like limbs for swimming
  109. vertebrate
    animals having a bony or cartilaginous skeleton
  110. water pollution
    pollution of the water in rivers and lakes
  111. whale
    largest mammal with a streamlined body and a blowhole
  112. zooplankton
    animal constituent of plankton
Created on Sat Feb 04 20:31:41 EST 2017 (updated Tue Apr 04 09:16:40 EDT 2017)

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