ZOOLONE Module 11-16 (Long Exam 3)

Diffusion in small or thin animals

Diffusion in small or thin animals

cells can exchange materials directly with the surrounding medium

Diffusion in most animals

cells exchange materials with the environment via a fluid-filled circulatory system

Gastrovascular Cavity

cavity that:

• functions in both digestion & distribution of substances throughout the body

• body well is only 2 cells thick

• some cnidarians and flatworms

Circulatory System

organ system:

• has circulatory fluid, interconnecting vessels, & muscular pump (heart)

• 2 types: open or closed

• may vary in number of circuits in the body

Open Circulatory System

type of circulatory system:

• insects, arthropods, & some molluscs

• NO blood vessels

• contains hemolymph

hemolymph

• circulatory fluid that bathes the organs directly

• instead of blood

Closed Circulatory System

type of circulatory system:

• annelids, vertebrates, & cephalopods

• contains blood that is confined to vessels & distinct from the interstitial fluid

Cardiovascular System

organ system:

• closed circulatory system of humans & other vertebrates

• has 3 main types of blood vessels

3 main types of blood vessels

artery, vein, & capillary

artery

type of blood vessel:

• blood away from heart

• branch to arterioles

vein

type of blood vessel:

• blood back to the heart

• branch from venule

capillary

type of blood vessel:

• network of vessels

• site of chemical exchange between blood and interstitial fluid

• connect arteries and veins

• exchange of oxygen and CO2

2 Types of Circulation

Single Circulation & Double Circulation

Single Circulation

type of circulation:

• bony fishes, rays, and sharks

• with a 2-chambered heart

• blood leaving the heart passes through 2 capillary beds before returning

• contains 2 types of circuits

2 types of circuits in Single Circulation

Gill capillaries & Body capillaries

Double Circulation

type of circulation:

• amphibians, reptiles, & mammals

• oxygen-poor & oxygen-rich blood are pumped separately from the right & left sides of the heart

• NO mixture of oxygenated and deoxygenated blood

• maintains HIGHER blood pressure in the organs

• contains 2 types of circuits

2 types of circuits in Double Circulation

pulmocutaneous/pulmonary circuit & systemic circuit

pulmocutaneous circuit

type of circuit in Double Circulation:

• in frogs

• blood will pass through skin & lungs to get oxygen

• enter heart to pump out oxygenated blood to the systemic circuit

systemic circuit

type of circuit in Double Circulation:

• exchange of gases in capillaries

• deoxygenated blood enter vein back to the heart

pulmonary circuit

type of circuit in Double Circulation:

• reptiles & mammals

• oxygen-poor blood flows through the ___ to pick up oxygen through the lungs

3 heart chambers in the frog

right atrium, ventricle, & left atrium

blood flow of frog

RA → V → PCC → LA → V → SC → RA

Evolutionary Variation in Double Circulation

• some vertebrates (amphibians and many reptiles) with double circulation are intermittent breathers

• different blood flow & number of heart chambers among animals

blood flow of mammals

RV → pulmonary artery → lungs → pulmonary vein → LA → LV → aorta → body tissues → capillaries → superior/inferior vena cava → RA → RV

Mammalian Heart

• enclosed in pericardium

• 4-chambered heart (2 atria, 2 ventricles)

• contains valves

atrium

heart chamber:

• 2 in both amphibians & mammals

• relatively thin walls

• collection chambers for blood returning to the heart

ventricle

heart chamber:

• thicker walls

• contract much more forcefully

• chamber for blood leaving the heart

valves

part of mammalian heart:

• prevent backflow of blood

• 2 types: atrioventricular & semilunar

atrioventricular valve

type of valve:

• tricuspid valve & bicuspid valve

• one on each side; between the atrium & ventricle

tricuspid valve

atrioventricular valve between RA & RV

bicuspid valve

atrioventricular valve aka "mitral valve" between LA & LV

semilunar valves

type of valve:

pulmonary& aortic ___ valves

pulmonary semilunar valve

semilunar valve between RV & pulmonary artery

aortic semilunar valves

semilunar valve aka "aortic valve" between LV & aorta

Cardiac Cycle

2 phases: systole & diastole

systole

contraction or pumping phase in the cardiac cycle

diastole

relaxation or filling phase in the cardiac cycle

heart rate

• pulse

• number of beats per minute

heart murmur

backflow of blood through a defective valve

autorhythmic

• rhythm of the heart

• can contract w/o the help of signals from the nervous system

sinoatrial node

node in the heart:

• pacemaker

• sets the rate and timing at the which the cardiac muscle cells contract

• found in RA

• impulses go down to the atrioventricular (AV) node

electrocardiogram

• recording of the impulses that travel during the cardiac cycle

• ECG / EKG

Blood

connective tissue consisting of several kinds of cells suspended in a liquid matrix called plasma

Plasma

component of blood:

• contains inorganic salts as dissolved ions

• contains plasma proteins

• also contains water & substances transported by blood

• 55% of blood

blood serum

component of plasma:

• plasma WITHOUT the proteins

• obtained from centrifugation

electrolytes

another term for inorganic salts in plasma

plasma protein

component of plasma:

• influence blood pH & help maintain osmotic balance between blood & interstitial fluid

• some function in lipid transport, immunity, & blood clotting

Cellular Elements

component of blood:

• includes: Red blood cells, white blood cells, & platelets

• 45% of blood

red blood cell

Cellular Element in the blood:

• erythrocytes

• transport oxygen

• contain hemoglobin

• do NOT have nuclei & mitochondria

hemoglobin

• iron-containing protein that transports the oxygen

• each molecule binds to 4 molecules of oxygen

• present in red blood cells

white blood cells

Cellular Element in the blood:

• leukocytes

• function in defense either phagocytizing bacteria & debris or by mounting immune responses against foreign substances

• found both inside & outside of the circulatory system

• has 2 types

2 types of white blood cells

granulocytes & agranulocytes

3 types of granulocytes

basophil, eosinophil, & neutrophils

basophil

type of granulocytes:

release histamine

eosinophil

type of granulocytes:

• attack parasitic worm

• contain antihistamine

neutrophil

type of granulocytes:

• responds to site of infection

• target bacteria

2 types of agranulocytes

lymphocyte & monocyte

lymphocyte

type of agranulocytes:

immune response in the body

monocyte

type of agranulocytes:

turn into macrophages, leave blood circulation, then turn into phagocytes

platelet

Cellular Element in the blood:

• thrombocytes

• cell fragments that are involved in clotting

• formed in the bone marrow

• release thromboplastin and the other clotting factors

coagulation

formation of a solid clot from liquid blood

inactive fibrinogen

converts into fibrin after a cascade of complex reactions

thrombus

• blood clot formed within a blood vessel

• can block blood flow

Lymphatic System

organ system:

• located along lymph vessels

• plays a major role in the body’s defenses

• for production, maintenance, and distribution of lymphocytes

• transport fat molecules from small intestines

thymus gland & bone marrow

body parts besides lymphatic system that are for production, maintenance, and distribution of lymphocytes

Gas Exchange

supplies oxygen for cellular respiration and disposes CO2

Partial Pressure

• pressure exerted by particular gas in a mixture of gases

• apply to gases dissolved in liquids such as water

air or water

Respiratory Media

less oxygen

amount of oxygen available in water than in air

respiratory surfaces

• large, moist surfaces for exchange of gases between their cells and the respiratory medium

• gas exchange in here takes place by diffusion

ventilation

moves the respiratory medium over the respiratory surface

skin, gills, trachea, and lungs

examples of respiratory surfaces

gills

example of respiratory surface:

• outfoldings of the body that create a large surface area for gas exchange

• aquatic animals use this for ventilation

countercurrent exchange system

• system that fish use with their gills

• blood flows in the OPPOSITE direction to water passing over the gills

• blood is ALWAYS LESS saturated with oxygen than the water it meets

tracheal system

example of respiratory surface:

• found in insects

• network of branching tubes throughout the body

• tubes supply oxygen directly to the body cells

• respiratory and circulatory systems are separate

lungs

example of respiratory surface:

• found in humans and other mammals

• infolding of the body surface

• circulatory system transports gases between the ___ and the rest of the body

• size and complexity correlate with an animal’s metabolic rate

Mammalian Respiratory System

system of branching ducts coveys air to the lungs

alveoli

• air sacs at the tips of the bronchioles

• sites of gas exchange

moist film of the epithelium

oxygen diffuses through the ___ and into capillaries

surfactants

• secretion that coats the surface of the alveoli

• keeps respiratory system moist

• if not, causes friction and body problems

Breathing

• process that ventilates the lungs

• alternate inhalation and exhalation of air

Amphibian breathing

breathing of animal:

• ventilates its lungs by positive pressure (forces air down the trachea)

• air does NOT go straight to lungs

• air goes to buccal cavity pouch first

• has 4 steps

positive pressure

pressure when animal forces air down the trachea

Avian Breathing

breathing of animal:

• have 8-9 air sacs that keep air flowing through lungs

• air flow in 1 direction

• requires 2 cycles of inhalation and exhalation

• ventilation is highly efficient

mouth, posterior air sacs, lungs, anterior air sacs, & mouth

flow of avian breathing

Mammal Breathing

breathing of animal:

ventilate their lungs by negative pressure breathing

negative pressure

pressure when animal pulls air into the lungs

lung volume increases

what happens as the rib muscles and diaphragm contract

spirometer

instrument to measure breathing and know efficiency of lungs

tidal volume

volume of air inhaled with each breath

vital capacity

maximum tidal volume

residual volume

air in the lungs after exhalation

medulla oblongata

• breathing control center in our brain

• regulates and depth of breathing in response to pH changes in the cerebrospinal fluid (CSF)

decrease in pH

pH level in the cerebrospinal fluid when there are rising levels of CO2 in blood

negative feedback mechanism in respiration

rising levels of CO2 in blood = decrease in pH → signals from medulla increase rate & depth of ventilation in lungs → CO2 level falls & pH rises (becomes basic)

low partial pressure of oxygen and high partial pressure of CO2

partial pressures of oxygen & CO2 in blood arriving in the lungs relative to air in alveoli

Respiratory Pigments

• proteins that transport oxygen

• greatly increase the amount of oxygen that blood can carry

hemocyanin with copper

respiratory pigment:

• in arthropods and many molluscs

• act as oxygen-binding component

hemoglobin

respiratory pigment:

• in most vertebrates and some invertebrates

• inside the erythrocytes

1:4

ratio of molecules of hemoglobin and oxygen it can carry

hint: 1 molecule for each iron-containing heme group