The Deep Sea Flashcards
Pressure at depth?
Enormous pressure due to weight of the water. At 5000 m pressure is 500 times greater than at the surface. Deep sea fish brought up to the surface rupture their organs and die.
How can Whales dive down so deep?
They go down with one breath of air. Continue dives can cause saturated tissue.
What is the chemistry of the ocean like?
Plenty of oxygen in solution due to deep ocean circulation. Salinities constant at 35.
What is the substrate like in the deep ocean?
It is mostly soft silts or clay. It builds up slowly from Marine snow.
0.1 - 1 mm per 1000 years
What is productivity like?
Falls rapidly as there is no photosynthesis. Nutrients come mostly from above and so it’s a very low supply.
What is life like in the deep?
The deep ocean is nutrient poor, cold, dark and vast.
What are some of the adaptations like in the deep ocean?
Advanced chemosensory capability Bioluminescent lures Red sensitive vision Big Jaws and teeth Huge/no eyes Headlights Slow metabolism
What are the defences like?
Bioluminescent decoys or camouflage Reflective colouring or black Free swimming Chemosensing Transparent
How do organisms mate in the deep ocean?
Parasitic males
10x smaller than females
Feed little after larval stage
Attach to females to ensure fertilisation
What are the alternative energy sources
Mid ocean ridges and hydrothermal vents
What are hydrothermal vents?
Super heated water 400°c
High concentration of sulphides
Abundance of hard substrate
What are tube worms?
Chemoautotrophs - use energy from chemicals instead of the sun to create needed sugars
What are methane seeps?
Deep underwater
Hypersaline water
Fine bubbles trickling up through the substrate
Methane bubbles from hydrocarbon deposits
Vast beds of mussels and tube worms
What can specialised bacteria do in methane seeps?
Convert methane into sugars for growth
Found primarily as symbionts in mussels but also as free living forms
