Topic 1: Lifestyle, Health and Risk Flash Cards

Topic 1

, Why do we need a

circulatory system ?

(mass transport)




QUESTION




To transport the essential substances
around
the body .




Larger organisms require a circulatory

system to overcome the limitations of

diffusion .




ANSWER

, Why does diffusion become

inefficient for larger organisms ?



C3 points)




QUESTION

SA : V
i
&
metabolic y



As the organism becomes larger :




↳ surface area to volume ratio decreases -




>
-
Diffusion distance increases
- Metabolic rate increases




ANSWER

, What are the features of a mass

transport system ?



14 points)




QUESTION




#
1 .
Network to more through
↳ veins ,
arteries , capillaries


2
. A medium for movement (a fluid ,
eg .


blood) 0 O 0




.
3 controlled directions >
S
↳ vessels have values =
preventing backflow

↳ moved along a pressure gradient


4
. Maintain of speed E
& elastic recoil of vessels
)
↳ contraction of heart

help maintain pressure gradient-speed



ANSWER

, What does it mean by single and

double circulatory system ?




QUESTION




i gle circulatory system
#
↳ The blood flows through the heart only once

completing a full circuit in the body

(eg . Fish



⑳be circulatory system
*
↳ The blood flows through the heart
nice in one


complete circuit




ANSWER

, What are the coronary arteries ?




QUESTION




They are arteries wrapped around the heart

and supply blood to the cardiac muscles




BLOOD- HEART
coronary
arteries




ANSWER