SE Practice - GenSci

The diagram shows the human heart and some of the blood vessels connected to it.

Before blood in W reaches Z it must ...

• gain glucose

• give up heat to the skin

• pass through capillaries

• travel to the head

The diagram shows a section through the heart. Which part pumps blood to the aorta?

• A

• B

• C

• D

Which chamber of the heart has the thickest muscle wall?

• left atrium

• left ventricle

• right atrium

• right ventricle

Which blood vessel has a high carbon dioxide concentration, a low oxygen concentration and a high blood pressure

• aorta

• pulmonary artery

• pulmonary vein

• vena cava

Why is the circulatory system of mammals described as a double circulation?

• Blood flows firstly through arteries and then through veins.

• Blood flows through the heart twice on one complete circuit of the body.

• In the heart, blood flows firstly through atria and then through ventricles.

• The atria and the ventricles contract alternately.

Which heart valves are open and which are closed when blood passes out of the right ventricle towards the lungs?

• bicuspid (mitral) valve closed, tricuspid valve open

• bicuspid (mitral) valve open, semi-lunar valve closed

• tricuspid valve closed, semi-lunar valve open

• tricuspid valve open, bicuspid (mitral) valve open

The diagram shows the human heart.

In which order does blood pass through the chambers during a complete circuit of the body after it returns from the lungs?

• Q → R → S → P

• Q → R → P → S

• P → S → Q → R

• P → S → R → Q

What are features of gaseous exchange surfaces in animals?

• thick-walled, dry, large area

• thick-walled, moist, small area

• hin-walled, dry, small areat

• thin-walled, moist, large area

What helps oxygen to be absorbed rapidly into the blood in the lungs?

• Air breathed in has less oxygen than air breathed out.

• Alveoli have thick walls and a large surface area.

• Alveoli have thin walls and a large surface area.

• The concentration of oxygen in the blood is higher than in the alveoli.

The diagram shows changes in air pressure inside the lungs during a complete cycle of breathing. Atmospheric pressure is 101kPa. Which position on the graph marks the point at which the ribs are beginning to be raised?

• A

• B

• C

• D