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level: final test

Questions and Answers List

level questions: final test

Question	Answer
more capillary beds open in the peripheral circulation of skin to increase blood flow transporting heat to the environment	Cooling
blood transports warmth to deep tissues or carries away excess heat to body surface. Mediated changes in microcirculation to control heating and cooling.	Circulation and thermoregulation
water more able to hold heat, flippers in cold water could lose top much heat. Mesh rete in intertwining network between outgoing arteries and returning veins, establishes counter current heat exchange. Heat in arteries is almost completely transferred to returning blood in veins forming heat blocks, by time blood reaches flippers there is almost no heat to be lost	Heat loss in flippers
is very sensitive, a specialised carotid rete at the base of the brain protecting against overheating. Many animals have highly folded tabernacle bones supporting extensive area of nasal membranes for evaporative cooling	Brain and heat loss
Turbinate bones, cool or heat incoming air and trap moisture. Heat- loss is highly variable due to wind and speed as little as 25% or as much as 400%.	Heat loss in birds
huddling in emperor penguins alone they burn 0.2kg of fat to keep warm in a huddle they only need 0.1kg.	Behavioural thermoregulation
Deep diving seals drop in heart rate form 125b.p.m. to 10b.p.m. slowing heart rate lessens need for blood stream, is followed by vasoconstriction. Lungs have 55% of usual blood flow heart 15%, diaphragm 5% brain 108% and cerebellum 93%. Mainly reducing flow to lungs.	Bradycardia
carry blood away form the heart, have 3 layers, flattened epithelium and supporting connective tissue, smooth muscle and elastic fibres. Elastic fibres allow expansion and pressure for blood flow. Small arteries move into arterioles and capillaries ,made up of a single layer of squamous epithelium. Are progressively smaller the further form heat with more smooth muscle and less elastin fibres.	Arteries
same layers as arteries but with thinner walls, less smooth muscle, larger lumen, and less elasticity. Has valves to prevent back flow. Low pressure in venous side. Larger veins between muscles. When skeletal muscles contract they compress veins promoting blood flow.	Veins
2 chambered, 1 atrium and one ventricle. Blood in nucleated . Some have lymph hearts that are low pressure and lack cardiac muscles.	Fish heart
3 chambered, 2 atrium and one ventricle. Have superficial lymphatic vessels	Amphibian heart
small biconcave discs RBC, and lack nuclei, have platelets that are not nucleated to clot blood, lymph is whiteish lumps of varying size and shape, many macrophages are present that phagocytise foreign material. Have lymph vessels that enter venous circulation where pressure is low.	Mammal blood
4 chambered. 2 atrium and 2 ventricles	Mammal heart
Blood pressure is high. Vessels have thin penetrative walls not connected to arteries. Lymph similar to cellular fluid and plasma important for transport of fatty acids. Moves slowly through vessels. Contains macrophages and lymphocytes. Lymph nodes only found in mammals. Reptiles have wider vessels and sacs. Must move from area of low pressure toa rea of high pressure (not a problem in fish.	Lymphatic system
4 chambered. Aortic arch to the right is to the left in mammals, Both mammals and birds have double circulation, pulmonary to and from lungs, and then one for to and from rest of body. Compared to mammals have large hearts, large cardiac output, fast heart rate and high blood pressure.	Bird heart
2 basic kinds of heart, 1. Turtles, snakes and lizards. 3 chambered. With ventricles and is incompletely divided. Has separate flow patterns. 2. Crocodiles. 4 chambered. Has ventricle’s and aorta and is completely divided. Has foramen. Is a stronger heart to aid in digestion, high carbon dioxide levels needed for stomach acid production.	Reptile heart
4 chambered. 2 atrium and 2 ventricles. Complete double circulation. A low-pressure pulmonary circuit, using right side of the heart. High pressure, systemic circuit using the left side. Walls of left side thicker and more muscular.	Mammal heart-
aided by heart pulling blood though gills. Detects sent and controls osmoregulation. Evolved from pharyngeal gill slits. Water flow bi-directional or tidal. Consists of visceral skeleton, blood vessels, cervical nerves, branchial muscles and epithelium. flow of blood opposite to water for countercurrent exchange.	Internal gills
develop from skin extending from the branchial area. Filaments of feather like projections, many have ciliated well-vascularised epithelium. Muscles wave the gills to provide ventilation in still water.	External gills-
skin breathing, effective for small vertebrates with low levels of activity in water or damp environments. Used by underdeveloped mammal marsupials and amphibians.	Cutaneous respiration
use cutaneous respiration, lungs and buccal breathing. Buccal or belly breathing is used as they lack a diaphragm and use positive pressure breathing. Lungs are simple ovoid elastic sacs with inner surface divided into faveoli.	Amphibians breathing
large and varied. Negative pressure breathing. Inhalation- the ribcage expands, and the liver is pulled back. Exhalation, the ribcage and liver move forward and compress, the lunges empty spent air is expelled.	Reptile respiration
air enter nostrils, trachea, syrinx, 2 primary bronchi, 75% into posterior air sacs and 25% into lungs, air form lungs into 7 other air sacs. Have 9 air sacs in total. Also used for heat control and shock absorbers. 2 cycles in breathing, 1st inspiration, through trachea into posterior air sacs 1st exhalation pushes air into parabronchi, 2nd inspiration air is pushed into anterior air sacs 2nd expiration air leaves.	Bird respiration
filters blood of toxic waste from protein breakdown and creates urea. Regulates nitrogen, water and iron balance. Structure differs depending on environment. Nephrons are used for filtration and reabsorption. Glomerulus masses of capillaries along with bowman’s capsule filter to blood. Kidney tubule collect the filtrate and conduct it to a longitudinal duct.	Kidney
hagfish, simple short tubule connecting to renal capsule then to excitatory duct. Lampreys and freshwater fish have longer and more differentiated tubules. Saltwater fish have reduced nephron and lost IS and DT. Amniotes have differentiated segments, the IS continues to the loop on Henle.	Nephrons
vary widely depending on species. Lampreys and cartilaginous fish – solid, bony fish- hollow, frogs and salamanders- soft and pleated, birds- only left side develops, solid with large amounts of connective tissue.	Ovaries
usually paired, may be partially fused as in sharks and rays. Elongate and slender in most vertebrates such as fish and snakes, compact and ovoid in frogs and amniotes. Mammal are enclosed in tough envelope and hang from body, pronounced septa for separation. Very sensitive to temp may retract closer or further from body to control temperature.	Testis
more resistant to dehydration and higher success for fertilisation than external fertilisation, courtship and egg disposition can be separated.	Internal fertilisation
egg laying, less pressure on mother to care for young, both parents can share responsibility in caring for growing baby.	Oviparity
young raised in stable environment, females not tied to site of egg disposition.	Viviparity
have epi-pubic bones to support pouch, have 3 vaginas, 2 lateral sperm passages and 1 medial parturition. Can have 3 young developing at once, one in uterine, one in pouch and one suckling form outside pouch. Birth a poley developed embryo to continue develop in pouch.	Marsupials reproduction