Chapter 42: Circulation And Gas Exchange Flashcards
Small molecules can move between cells and their surroundings by
Diffusion
Random thermal motion
Diffusion
Diffusion is only efficient over ________ distances
Small
In most animals, the circulatory system is functionally linked to the ___________ ___ ______ with the environment and with body cells
Exchange of gases
Some animals lack a ___________ system
Circulatory
Cnidarians have elaborate _____________ __________
Gastrovascular cavities
Gastrovascular cavities function in _________ and __________ of substances throughout the body
Digestion; distribution
The body wall that encloses the gastrovascular cavity is only ___ cells thick
2
What specimen have a gastrovascular cavity?
Flatworms
What 2 things do Flatworms have that minimize diffusion distances
Flat bodies; gastrovascular cavity
What 3 things do circulatory systems have?
Circulatory fluid
Set of interconnecting vessels
Muscular pump, the heart
The circulatory system connects the ________ that surrounds cells with ________ that exchange gases, absorbs nutrients, and dispose of wastes
Fluid; organs
Circulatory systems can be _______ or _________
Open; closed
In _________, other arthropods, and some molluscs, have circulatory fluid called __________
Insects; Hemolymph
Bathes the organs directly in an open circulatory system
Hemolymph
Hemolymph is a part of a ______ circulatory system
Open
Blood is a part of a ________ circulatory system
Closed
Is confined to vessels and is distinct from the interstitial fluid
Blood
Name 3 groups that have closed circulatory systems
Annelids
Cephalopods
Vertebrates
Allow organisms to use less energy than needed
Open systems
Allow organisms to grow larger
Closed systems
Allow organisms to be more active due to effective delivery of oxygen and nutrients
Closed system
Regulate the distribution of blood to different organs
Closed system
What is a closed circulatory system in humans and some vertebrates called?
Cardiovascular system
What does the cardiovascular system include?
Heart
Blood vessels
What are the 3 main types of blood vessels
Arteries
Veins
Capillaries
Blood flows ______ way in these vessels
One
Arteries branch into _________ and carry blood ______ ______ the heart to __________
Arterioles; away from; capillaries
AKA network of capillaries
Capillary beds
Sites of chemical exchange between the blood and interstitial fluid
Capillary beds
Capillary beds have chemical exchange between the _____ and ________ ________
Blood; interstitial fluid
_______ converge into veins
Venules
Return blood from capillaries to the heart
Veins
What are distinguished by the direction of blood flow, not by ____ content
Arteries; veins; O2
Vertebrates hearts contain ____ or more chambers
2
Blood enters through _______ and is pumped out through ____________
Atria; ventricles
Sharks, rays, and bony fish have _________ circulation with a ____-chambered heart
Single; 2
In single circulation, blood leaving the heart passes through ____ capillary beds before returning
2
What groups have double circulation?
Amphibians
Reptiles
Mammals
In double circulation, oxygen-poor blood is pumped from the _______ side of the heart in ___ circuit
Right; 1
In double circulation; oxygen-rich blood is pumped from the _____ side of the heart in a _________ circuit
Left; separate
Oxygen-poor blood flows through the __________ ________ to pick up oxygen through the _______
Pulmonary circuit; lungs
What group(s) have oxygen-poor blood flow through pulmonary circuit
Reptiles and mammals
Oxygen-poor blood flows through the __________ ________ to pick up oxygen through the _______ and ________
Pulmocutaneous circuit; lungs; skin
What group(s) have oxygen-poor blood flow through pulmocutaneous circuit
Amphibians
Oxygen-rich blood delivers oxygen through the _______ circuit
Systemic
___________ circulation maintains higher blood pressure in the organs than does _________ circulation
Double; single
