BIOL 233 Animals

What 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