ESSENTIAL  BIOLOGY  LEARNING  GUIDES (HOMEWORK, REVIEW)

Topics 6.2, 6.4 Transport (Circulation), Gas Exchange (combined document for both topics)

SUPPORT MATERIAL FOR UNIT (HOMEWORK, CLASS  DISCUSSION)

Powerpoints (S Taylor) for topics 6.2, 6.4  Clegg reading: pp 184-193, 204-209 

6.2 Transport (Circulation )

valves in the heart maintain one-way flow of blood

valves are also found in the veins of the legs - Why??

HOW DO THE VALVES WORK?

WHAT STARTS THE SYSTEM? MYOGENIC SINO-ATRIAL NODE.  NOTE WHAT IS MUSCLE AND WHAT IS NERVE TISSUE IN THE FOLLOWING (click on image to set animation)

WHAT CONTROLS THE RATE?
     INCLUDE ROLES OF CARBON DIOXIDE, CHEMORECEPTORS IN THE BLOOD, 
    THE MEDULLA  OBLONGATA IN THE BRAIN, THE VAGUS NERVE, 
     EPINEPHRINE, AUTONOMIC CONTROL,   NEGATIVE FEEDBACK.

HEART MUSCLE NEEDS ITS OWN SOURCE OF BLOOD - CORONARY ARTERIES!

ARTERIES VS. VEINS...STRUCTURE/FUNCTION

BLOOD COMPOSITION AND FUNCTION - SEE ALSO BLOOD TYPING LAB.

CAN   YOU   LIST   5   BIOCHEMICALS   CARRIED   DIRECTLY   IN   THE   PLASMA?  
TWO   BIOCHEMICALS   CARRIED   INDIRECTLY   BY   BLOOD CELLS?  
ONE   FORM   OF   ENERGY   CARRIED   BY   BLOOD?

6.4 - Gas   Exchange   (respiration)

Gas exchange (a) oxygen (red) from lungs TO capillary, (b) from capillary TO body cells. Carbon dioxide (blue) is shown in the reverse path

Tissue level and cellular level diagrams of lung structure

also look at the torso model in class and diagram below - note the internal and external intercostal (in between the ribs) muscles - which contracts with inspiration and which with expiration?

Photomicrograph of lung tissue - note the interconnectedness of lung and capillary tissues

also look at lung model in class and diagram below - what happens as the diaphragm contracts?

diaphragm contract - expand thoracic volume, diaphragm relaxes - decrease thoracic volume

external intercostals contract - expands thoracic cavity internal intercostal contract - decreases volume in thoracic cavity