CHAP 5 TRANSPORT IN HUMANS

Question 1

what are the main blood vessels to and from the heart,lungs,liver and kidney?

Answer 1

Pulmonary artery- carries deoxygenated blood from heart to lungs [ right ]
Pulmonary vein- oxygenated blood from lungs to heart [left]
Aorta- oxygenated blood from heart to rest of body.
Hepatic artery- oxygenated blood from heart to liver
Hepatic vein- deoxygenated blood from liver to heart to vena cava
renal artery- oxygenated blood from heart to kidney
renal vein-deoxygenated blood from kidney to heart
hepatic portal vein- absorbed food subs & nutrients to liver

Question 2

state the structures of ARTERY [4]

Answer 2

• carries blood away from the heart
  thick muscular & elastic walls - to withstand constant high pressure of the blood as it gets pushed out from the aorta
  no valves- high pressure & fast pace blood
• smaller lumen as compared to vein

Question 3

State the structures of the vein [4]

Answer 3

-carries blood to the heart
- thin, less muscular & less elastic walls - lower blood pressure , blood runs more slowly & smoothly.
valves present- to prevent back flow of blood due to slower pace
- large lumen

Question 4

State the structures of CAPILLARIES [4]

Answer 4

• exchange nutrients+oxygen with tissues & cells
• one cell thick
• takes away waste products [ CO2 ]
• lower blood pressure

Question 5

roles & adaptations of RBC

Answer 5

• carry O2 from lungs to body tissues so cells can use in cellular respiration.
• contains red pigment ( haemoglobin ) -> binds with O2 to form oxyhemoglobin [ will separate when it reaches tissues low in O2 and diffuses into the tissues ]
  ADAPTATIONS
• no nucleus
• biconcave shaped- more surface area to volume ratio for haemoglobin to bind with oxygen for better absorbing or O2

Question 6

Roles & adaptations of WBC

Answer 6

• defends us against infections
  -phagocytosis-> engulf pathogens
  produce antibodies -> bind to pathogen & help destroy them
  Lymphocytes-> recognise foreign particles & destroy bacteria and viruses , causes bacteria to clump together for easy ingestion by phagocytes + neutralise toxins produced by bacteria

Question 7

Roles & adaptations of Platelets [2]

Answer 7

• nu nucleus
• Clotting - converts soluble protein fibrinogen to insoluble fibrin threads which entangle blood cells & forms a clot -> prevent excessive loss of blood & entry of harmful bacteria

Question 8

roles & adaptations of PLASMA [2]

Answer 8

• makes blood liquidly to flow
• carries everything ( nutrients, RBC,WBC,platelets, waste products, hormones , urea)