14-OcFA11-PelagicWeb

14-OcFA11-PelagicWeb - Pelagic Marine Organisms Ocean...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Ocean provide a stable environment conducive to life… Relatively constant temperature Constant moisture Structural support (no skeleton needed) Dissolved nutrients and salts Transportation mechanism for food and waste *Life probably began in the oceans Special Conditions to which Marine Life must adapt: Darkness Cold Temperature Salinity Pressure Staying Afloat (as well as for reproducing, eating, avoid being eaten. .etc. not unique to marine environment) Pelagic Marine Organisms
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Adaptations Adaptations For a Marine Life to cope with: Darkness Most of the ocean is dark (98%) But they need to find food, find each other, navigation Large Eyes/light sensitivity Large eyes let in more light Bioluminescence (also Iridescence) Found commonly in deep sea organisms Produced by symbiotic bacteria kept in cells self-luminous cells: photophores Counter-illumination Echolocation Mostly marine mammals: dolphins, whales interpret echo returns and in terms of distance, size, texture and swimming direction of prey Make a rapid clicking noise with an specialized organ (not vocal cords) Sound received in lower jaw and transmitted to inner ear May use sound to stun or kill prey Volume: dolphins - 230 decibels, sperm whales - 260 d, military jets- 130 d Electrosensing ampullary organs - receptor cells ampullae of Lorenzini form a complex and extensive sensory system around a shark's head.
Background image of page 2
Temperature – Smaller range than on land, relatively constant Generally cold (2-3 degrees C) Cold blooded - most marine animals – Internal temp = external temp – Don’t have to expend energy heating Tend to move in short quick bursts – Have special enzymes that operate at lower temperatures – Fish: Heat generated by swimming muscles retained by specializations of the circulatory system – Have special fats that remain liquid at low T (unsaturated. .with double bonds e.g. omega-3 Warm blooded – more complex animals: mammals (some fish) Stable, high internal temperature – Advantage: Can move, eat, reproduce faster – Insulating layer of fat (blubber) keeps body warm and buoyant dense layer of hollow fur traps a layer of air next to the skin so skin never gets wet. Large size: Reduces surface area to volume ratio, less heat loss to surroundings – Controlling of blood circulation: Vasodilation controls where and when blood goes Countercurrent heat exchange in limbs allows cold blood returning to the body core from extremities to be warmed by exchanging heat with closely packed arteries going to the periphery. http://www.fed.cuhk.edu.hk/~johnson/teaching/homeostasis/homeostasis.htm
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 13

14-OcFA11-PelagicWeb - Pelagic Marine Organisms Ocean...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online