Life on Planet Earth Notes 2 25 14 Announcements quiz 5 Friday due at 8 pm Pick up writing assignment due March 9 2014 at 8 pm Exam 2 March 6 2014 Oceans Watched TED and looked at animals that glow under water some use it to hypnotize predators Only explored 3 of what is in the ocean Looked at shallow water animals octopus moving across the reef fits in immediately Squids fighting white means they are aggressive squid has itself split in half so the other males are warned off but the female does not see that he is doing that Octopus can make themselves look like a rock and blends right into the background and moves through the waves Octopus can match color surrounding texture pattern to blend in so well to anything 97 5 of all water on earth is saltwater salt input comes from land runoff salt levels are maintained over time maintained by salt removal pore water binding to minerals plate tectonics recycle land to produce salt when the lands keeps moving and changing Distribution of Marine Life Ocean life is not evenly distributed Most of the open ocean is like a watery desert hardly any living Most of the life in the ocean is found near the continents above organisms the continental shelf Nutrients are the limiting factor Stirred up from the bottom by currents and storms Richest areas of life are in the temperature climates Life strongly fluctuates with the seasons Nutrient availability stimulates entire food web The Photic Zone Zone where the light enters the water but the amount of life that reaches the bottom of the ocean floor is minimal Many photosynthetic organs that need light from the sun are around 50 meters deep Light can not go in if the water is not clear The photic zone is where the light penetrates through the water 90 of all ocean life is found here high productivity Extends 100 200 meters below the surface Depending on water clarity Marine plant adaptations Plants must be able to float to remain within the photic zone to photosynthesize Most are unicellular and microscopic Small size facilitates transfer of nutrients into wastes out of cell Temperature adaptations Fish Cold blooded same temperature as surrounding areas Don t require as much oxygen or food as warm blooded animals Warm blooded means they have to adjust their own body temperature according to their surroundings Mammals Warm blooded generate internal body heat Insulates bodies with blubber fat insolation Blubber fat and connective tissue Artic bowhead whale has blubber layer of 2 feet thick only way it can survive Dealing with salt water Sea water is saltier tan animal body fluids It pulls water from body tissues by a mechanism called osmosis Osmosis is the movement of water molecules though a semipermeable membrane from higher to lower concentrations Hypertonic has more salt or sugar on the outside ex book has more information than your brain has learned yet Brain is hypotonic Marine vs freshwater fish adaptations Salt water adaptations Marine fish body fluids are less salty than the water Osmotic water loss Drink sea water Salt excretion by gills eliminate salt Low urine production by kidneys Sea birds drink salt water remove salt with salt glands sneeze out salt through nose Whales do not drink salt water blubber forms barriers to osmosis and get both salt and water from the organisms they eat don t drink water that is why they blow it out of their blowhole Freshwater fish Body fluids are more salty than the water Osmotic water gain Does not drink water Acquiring oxygen Oxygen is dissolved in seawater is 50 less than that in air Marine animal still need oxygen to survive Fish have gills that work by countercurrent exchange An exchange between two flows going in opposite directions Fish taste different depending if they are freshwater or salt water because salt water fish have a saltier taste Marine mammal oxygen adaptations Use oxygen efficiently Exchange 90 of the air in each breath and their blood chemistry high red blood cell count allows greater oxygen retention Have a high tolerance to lactic acid and carbon dioxide Their muscles can work anaerobically without oxygen while they hold their breath Can tolerate a lot of atmospheric pressure at great depths it would crush our bones Our lungs and ribs are collapsible minimizing our air spaces Adaptation to water pressure Pressure increases rapidly with depth Adaptations Most marine organisms lack large compressible air pockets inside their bodies Water filled bodies exert the same amount of pressure as is pushing inward so marine organisms do not feel the high pressure at depth Video secret life of plankton What does plankton mean Came from a batch of a million eggs Comes from the greek word wandering Comes in all sizes Zooplankton are drifting animals Teaspoon of sea water can contain almost a million living sea creatures Phytoplankton single celled life that are the base for the largest food web in the world Look up krill and copepods Even scientists do not know who eats who because the food web is so complex Dead zones The influx of nutrients from land use agriculture is called eutrophication Started around the 1970s which is when the green revolution started 2008 there were over 400 of them plenty on east coast of the united states How are dead zones formed Fresh river water brings in nutrients to ocean allow algae to grow rapidly and then they run out of space and nutrients and die Dead algae forms cover on top of continental shelf so no light can come in Video deep ocean mysteries and wonders notes Corals are full of life big small dangerous harmless animals of all kinds There is fire deep in the ocean going on everywhere the rocks produce the fire There are ponds lakes and rivers in the bottom of the ocean and there are animals that only live in the water There is a mountain range in the middle of the ocean largest mountain range and we have not seen it much at all Largest waterfall in the planet is in ocean near Iceland To explore ocean at these parts need team and technology Took 2 hours for submarine to reach the bottom of the ocean Find hot springs in the deep ocean where the mountains are and found more life and density than the tropical rainforest There is not always the need for sunlight for life The titantic is a really good place to study life since it has been underwater for so long animals move in and out Everything we do in life is somehow controlled by the ocean which has only been explored 5 Each video is available to watch