Practical 6 Flashcards
What are circulatory systems used for?
They are sued for the internal transport of a wide range of materials
What do electrocardiograms (ECGs) show
They show the fluctuations in the potential that represent the coordinated waves of electrical potential moving through the heart muscle
What does the height of the wave indicate in an ECG diagram?
The height of the wave is an indication of the amount of electrical activity.
What effect does standing up have on heart rate?
Very slight increase in heart rate
In the dive response did the heart rate change?
Heart rate initially increases due to shock of diving into water, but then decreases below-average heart rate to conserve oxygen
What circulatory changes have occurred to cause the heart rate change in a dive response?
Vasoconstriction occurs due to an increased pressure under water, making it harder for blood to travel around the body
Intracellular transport
usually protoplasmic movement, which supplements diffusion
Movement of external medium through animal (circulatory system)
Water passes through body channels and may be propelled by ciliary, flagella or muscular activity
What animals have a movement of external medium circulatory system?
Sponges and cnidarians
Movement of body fluids by somatic musculature (circulatory system)
It is quite literally a circulation of body fluid
Nematodes, bryozoans and rotifers circulaotory system?
Circulation of body fluids in a pseudocoelom
Echinoderms, annelids, sipunclids and chordates circulatory system?
Some transport, associated with body movements in mesodermally lied coelom
Circulatory system in molluscs and arthropods with an open haemocoel?
Much fluid propulsion is by movement of body musculature
movement of haemolymph in open systems (circulatory system)
A circulatory system in which a heart pumps haemolymph through vessels and a haemocoel derived from the primary body cavity.
Haemolymph passes from the vessels into tissue spaces and returns via sinuses to the heart.
The movement of Haemolymph in open systems is used by which animals?
Most arthropods, many molluscs and ascidians
Movement of blood in a closed vascular system (circulatory system)
A closed system of tubes, with one or more pumps.
Blood comes into close association with the body tissues via capillary networks
Movement of blood i a closed vascular system is used by which animals?
Oligochaetes, many polychaetes, leechs, nemerteans, cephalopod, molluscs, holothurian echinoderms and vertebrates
How do oxygen and food pass from the external medium into the cells of sponges and cnidarians?
Through diffusion
In which direction does the blood flow through the dorsal vessel of the polychaete worm?
Blood flows forward in the dorsal vessel, and returns down the body in the ventral vessel
How does transported material get in and out of the closed circulatory system?
Through a specific exchange site.
Lungs or gills for oxygen, gut for nutrients
What is the relationship between the efficiency of a circulatory system and metabolic rate?
Higher efficiency allows for higher metabolic rate, as there is no mixing of oxygenated and deoxygenetated blood
Difference between mammalian hearts and python hearts?
Mammalian hearts are a lot more muscular and fatter filled.
Four chambered in mammals whilst the python has a 3 chambered heart.
What is the foramen of Panizza?
It is the hole the connects the right and left aorta in the heart of crocodillia.
What is the function of the foramen of Panizza?
When it opens, it allows the mixing of pulmonary and systemic circuits.
May allow blood to bypass heart during diving to lengthen time croc can be underwater.
