Q&A - PSLE Science

[atutor2001]

starlight1968sg:

Hi atutor2001,

Thanks so much for sharing.
Air enters through our nose and goes into our lungs through the windpipe.
When air reaches the alveoli which are covered by the thin walled capillaries, oxygen passes through the thin walled capillaries and enters the bloodstream. This oxygenated blood then leaves the lungs and goes to the heart before it is pumped to the rest of the body.
At the same time, carbon dioxide from the blood, passes through the thin walled capillaries and reaches the alveoli. The air then is rich in carbon dioxide is exhaled out from the lungs.

Am I correct? I am unsure about the exchange of gases at the alveoli part.

Thanks.

Hi starlight1968sg

I share the same idea as you.

[starlight1968sg]

Hi,

I need some help on \"human skeleton\" in Q11 of
http://www.orlesson.org/orp/09Sc/2009-Sc-SA2-MGS.pdf.

Is the option 3 (model ans) correct?
Why?
Many thanks.

[Sonshine]

starlight1968sg:

Hi,

I need some help on \"human skeleton\" in Q11 of
http://www.orlesson.org/orp/09Sc/2009-Sc-SA2-MGS.pdf.

Is the option 3 (model ans) correct?

Many thanks.[/img]

Yes, it is no. 3.

[tianzhu]

Hi starlight1968sg


I hope I am referring to the right question, Q11 from MGS P5 SA2 2009.
http://www.orlesson.org/orp/09Sc/2009-Sc-SA2-MGS.pdf

In the topic on Skeletal System, primary students learnt that a joint is a place where two bones are connected. There are two different types of joints, fixed (immovable) joints and movable joints.

An example of fixed joints is those that are found in the skull. Two different kinds of movable joints are covered in the syllabus, they are hinge joint( elbows. Knees, fingers, toes) and ball and socket joint (shoulders and hips)

With this information, we should be able to answer Q11; the answer is option (3)

Best wishes

[starlight1968sg]

tianzhu:

Hi starlight1968sg


I hope I am referring to the right question, Q11 from MGS P5 SA2 2009.
http://www.orlesson.org/orp/09Sc/2009-Sc-SA2-MGS.pdf

In the topic on Skeletal System, primary students learnt that a joint is a place where two bones are connected. There are two different types of joints, fixed (immovable) joints and movable joints.

An example of fixed joints is those that are found in the skull. Two different kinds of movable joints are covered in the syllabus, they are hinge joint( elbows. Knees, fingers, toes) and ball and socket joint (shoulders and hips)

With this information, we should be able to answer Q11; the answer is option (3)

Best wishes

Thanks, and Sonshine who have replied.
Yes, I know movable and immovable joints.
Guess I have to read up more about these movable joints to know their differences.

[MOE Hater]

Corect me if I am wrong......The ball and socket joints allows bones to move intwo directions while the hinge joint can move only one direction? :idea:


MTIA :?:

[starlight1968sg]

MOE Hater:

Corect me if I am wrong......The ball and socket joints allows bones to move intwo directions while the hinge joint can move only one direction? :idea:


MTIA :?:

Yes, I am confused with the number of directions the movable joints can move.

[Nebbermind]

you can get some help http://www.bbc.co.uk/science/humanbody/body/factfiles/joints/hinge_joint.shtml

[starlight1968sg]

Nebbermind:

you can get some help http://www.bbc.co.uk/science/humanbody/body/factfiles/joints/hinge_joint.shtml

Thanks a lot; very useful info from the link:

Ball and socket joints, like your hip and shoulder joints, are the most mobile type of joint in the human body. They allow you to swing your arms and legs in many different directions.

Hinge joints, like in your knee and elbow, enable movement similar to the opening and closing of a hinged door.

Option 3 in that question becomes very obvious.

[PSLEmom]

Isn’t Skeletal system excluded for this year’s PSLE?