Studied by 4 peopleWhat dose the circulatory system transports
Oxygen to all cells. Nutrients from the digestive system to all cells. Waste products from cells and returns them to the respiratory, digestive, and urinary systems for disposal. Hormones from where they are secreted to their target organs
What two processes is the circulatory system is involved in
immune response and thermoregulation
Sponges and most cnidarians use ______ as their circulatory fluid
water
In invertebrates with a pseudocoelom, the ________ acts as the circulatory fluid
coelomic fluid
In an open system the _______________ is circulated around the body
extracellular fluid
Circulatroy system of molluscs
There is a vessel from the heart that supplies the gills and one that supplies the rest of the body.
What is the circularoty fluid in insects?
Haemolymph
Lymph contains
Cancer cells, Damaged cells, Fats, Bacteria and viruses, White blood cells (lymphocytes)
Blood pressure in veins is significantly ________ than in arteries
lower
How is blood moved the great distances necessary in bipeds?
Venous pressure combined with muscles in the legs squeezing the veins, and the valves in veins.
Plasma
carries endocrine molecules, proteins, solutes, that includes nutrients, gasses, and wastes
Formed elements
Erythrocytes, thrombocytes, leukocytes
Capillaries
where gas, nutrient and waste exchange happens between the blood and the cells.
Blood slows down when passing through capillaries because
of the small diameter of the vessels, which allows for more time for the exchange of materials
Continuous capillaries
complete basement membrane and continuous endothelium with intercellular clefts. Least amount of exchange. Found in muscle, skin, lungs and CNS
Fenestrated capillaries
complete basement membrane and continuous, fenestrated endothelium. Greater exchange. Found in endocrine glands, small intestine and kidneys.
Sinusoid capillaries
discontinuous basement membrane and discontinuous, fenestrated endothelium. Maximum exchange. Found in liver, spleen and bone marrow
The circulatory part of the lymphatic system consists of
lymphatic capillaries, vessels and ducts
Lymph ducts empty back into
the bloodstream at the junctions of the jugular and subclavian veins on each side of the body
How is lymph moved?
By movement of the body and in "lymph hearts" in amphibians, reptiles and some birds.
The most ancestral vertebrate circulation system is found in
Fish, they have a single circuit and a two chamber heart
In birds and mammals the sinus venosus evolved into
the sinoatrial node
In birds, mammals, and crocodilians the conus arteriosus becomes incorporated into
the ascending aorta and pulmonary trunk
What caused the need for a second pulmoary circuit?
The developments of lungs
Double circulation
One circuit goes to the lungs, where the blood is oxygenated. This oxygenated blood returns to the heart to be circulated to the body. Found in amphibians, reptiles, birds and mammals
The trend in evolution of the vertebrate heart is towards
increasing separation of oxygenated and deoxygenated blood
Amphibians have how many chambers in their heart?
three, with two atria and one ventricle. Oxygenated and deoxygenated blood don’t mix in the atria and ventricle is partly divided to reduce the mixing.
Why does fluid need to return from the lymphatic system back into the bloodstream?
To maintain normal blood pressure and volume and prevents fluid from building up in tissues
Edema
Fluid build up in the tissues (swelling)
Lymph nodes
Filter out all the waste from the lymph
The evolution of endothermy is thought to be related to
The increased efficiency of the heart of birds and mammals
What four types of tissues are found in arteries, veins, arterioles, and venules?
Endothelium, Elastic fibers (two layers in arteries), Smooth muscle (thicker in arteries), Connective tissue
Why are there two layers of elastic fibers in arteries?
Arteries are under much higher and need to be able to recoil and not burst each time a pulse of blood comes through.
What does the muscle layer in blood vessels allow for?
Vasoconstriction and vasodilation
Vasoconstriction
lowers blood flow through a particular artery
Vasodilation
Increase blood flow to a particular artery
How many hearts do Cephalopods have?
three, two branchial hearts send blood to the gills and a systemic heart that sends blood to the body
How many hearts do annelids have?
most have five hearts, blood flows away from the heart through ventral vessels and returns through dorsal vessels
What are the advantages of a closed circulatory system?
Higher pressure and more rapid blood flow. Blood flow can be targeted to individual organs. Blood flow to organs can be adjusted depending on the need of the body
How do lizards and snakes keep oxygenated and deoxygenated blood separate?
They have a septum that partly divides the oxygenated and deoxygenated blood in the ventricle.
How can the efficiency of gas exchange be improved?
By increasing surface area, decreasing distances across the respiratory surfaces, and increasing gas concentration differences.
What type of respiration can very small and thin organisims use?
Diffusion across a moist surface
Gill filaments
Made up of multiple thin lamellae connected to capillaries.
How does respiration occur in the gills?
Water flows over the gill lamella opposite to blood flow resulting in counter current reparation
Buccal pumping
Ventilation using the buccal cavity and the operculum; meaning they can breathe at rest. Ex. bony fish
Ram Ventilation
Tuna and sharks swim constantly with their mouths open to ensure a constant flow of water over their gills
Swim bladder
Seen in carps and salmonids, branched off of the esophagus, highly vascularized. These fish will gulp air into their swim bladder and gas exchange will occur across its surface. Can be used to control buoyancy
Labyrinthine organ
Vascularized expansion of the first gill arch through which they exchange gas. Ex. Betta fish
What allows Mudskippers to survive out of water?
They have a highly vascularized pharyngeal cavity that can be used for cutaneous respiration
What two methods do Lungfish use for respiration?
They have actual lungs connected to their pharynx. They also have gills but most supplement this oxygen with oxygen from the lungs
What do all terrestrial creatures require for gas exchange?
Moisture
What type of respiratory system do most insects have?
Tracheal system
What type of lungs do spiders have?
Book lungs
What type of lungs do amphibians have?
Faveolar and they are ventilated through positive pressure
What type of lungs do reptiles have?
Faveolar and they are ventilated through negative pressure
Why do reptiles and amphibians not have large complex lungs?
Their metabolism is lower due to them being ectothermic.
Why do birds and mammals have large, complex lungs with large surface areas?
to provide sufficient oxygen for their metabolism and activities
Where does gas exchange occur in mammal lungs?
Across the thin walls of the alveoli.
Negative pressure ventilation
Created by the contraction of the diaphragm and expansion of the chest wall. Ex. mammals
What is a disadvantage of mammal lungs?
The alveoli cannot be completely emptied, so there it always some residual air left inside them
What makes bird lungs more efficient?
The flow-through design means there is no residual air left in the lungs and gas is being exchanged constantly.
What part of bird lungs expand and contract?
The air sacs
What muscles do birds use to expand and contract their thoracoabdominal cavity?
Intercostal and abdominal muscles
Describe the active phase in bird respiration
The muscles contract to squeeze air out of the sacs. When the muscles relax, air is drawn into the sacs
Why do crocodilians have parabronchial lungs?
because when crocodilians evolved the atmosphere had less oxygen than it does currently
What repiratory pigment transports oxygen?
Haemoglobin
Each molecule of haemoglobin can bind up to _______ molecules of oxygen
four
Hemerythrin
Uses iron to bind oxygen, but does not have heme groups, despite its name. It binds oxygen as OOH- as opposed to O2
Osmolarity
The number of osmotically active moles of solute per litre of solution
Tonicity
The ability of a solution to change the volume of a cell by osmosis
If a cell is put in a hypertonic solution it will
lose water and shrink
If a cell is put in a hypotonic solution it will
take in water and swell
If a cell is put in an isotonic solution
there will be no movement of water
Osmotic gradient
The difference in concentration on both sides of a semipermeable membrane.
Osmoconformers
Have body fluids that are isotonic to seawater preventing an osmotic gradient. Most marine invertebrates
Osmoregulators
Maintain constant blood osmolarity while having different concentrations than their surroundings. All other vertebrates
Bony fish and tadpoles excrete ammonia through
diffusion through their gills
Cartilaginous fish, adult amphibians, and mammals excrete
urea
Flatworm excratory system
Have protonephridia (tubules) that branch throughout their body into flame cells. Cilia in the flame cells move fluid throughout the body. Water and metabolites are reabsorbed in flame cells and wastes are excreted through pores
Annelid excratory system
Have nephridia that open to both the inside and outside of the body. Coelomic fluid is filtered into the funnel shaped nephrostomes. As filtrate is moved salt is reabsorbed through active transport
Malpighian tubules
Found in insects, draw waste molecules and potassium ions through active transport. The resulting gradient draws water into the tubule and is later reabsorbed with the potassium ion in the hindgut.
Nitrogenous waste in insects
uric acid
Nephron
The structural unit of the vertebral kidney. Filters blood under pressure to create tubular fluid, wastes are secreted into the fluid, and other molecules, ions, and water are reabsorbed. Molecules are them secreted from the blood
What is the advantage to the vertebrate unrinary system?
It can be adapted to many environments and unknown wastes can still be filtered out of the system
Amphibian kidneys are the same as
Freshwater fish, they produce dilute urine and retain electrolytes through active transport of sodium ions across the skin from the water
Frogs have a large bladder where they
store urine and reabsorb water while they are in terrestrial environments
Due to their environment marine reptiles lose _______ and absorb _________
Water, salt
How do marine reptiles eliminate salt?
salt glands located around the nose or eyes.
True or false, marine reptiles produce isotonic urine?
True
Terrestrial reptiles nitrogenous waste
uric acid, this requires little water that is later absorbed by their cloaca
Sponges have _________digestion
intracellular
Blind sac digestion
Digestive enzymes are released into the cavity and food is broken down and absorbed by the cells lining the cavity. Ex. cnidarians and platyhelminths
Tubular gut
Seprate mouth and anus allowing for specialization. Different regions have different functions
The most primitive tubular gut is found in
Nematodes
The first creature to show specialization in the gut is
Earthworms
Oral Cavity
First part of digestion, mechanical fragmentation
Dentition patterns reflect
diets
Tongues are used to
obtain food, mix it with saliva, and manipulate food for swallowing
Pharynx
Extends from the soft palate to the esophagus, it is muscular and moves food into the esophagus.
Many fish filter feed with
gill rakers which are located in their pharynx
Note 
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