forestcadee:

Hi, need help on the following question. Thanks.


A boy was playing a football game. Which of the following body systems interacted together to enable him to play the game?

A: Digestive system
B: Circulatory system
Respiratory system

1) A & C only
2) A & B only
3) B & C only
4) A, B & C

Digestion breaks down food into smaller pieces for the digested food to be transported by blood in the circulatory system to all the cells in the body. Respiration helps to release the energy 'locked' in the digested food to the cells. Answer should be (4) A, B & C

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Jolene is the unaffected carrier daughter while Joshua is the affected son. For a person to have a recessive disorder, it requires two copies of the mutated genes. Males are affected by a single X-linked recessive gene from their mother. This is because they do not have a second X chromosome to override the recessive trait.

In conclusion, a woman who is a carrier of a X-linked recessive disorder has a 25% chance of either having an unaffected son, or having an unaffected daughter, or having having an unaffected daughter who is a carrier, or having an affected son.

The question asked for which of the children is a carrier of the genetic disorder traits. So the correct answer is Jolene only. Joshua is the affected son.

shirley.tamzil:

Which part of a plant is needed to make food?

1. Flower
2. Roots
3. Leaf
4. Stem

DS answered 3. Leaf, but the answer sheet shows 1. Flower as the answer. Not sure why, so would like to check with the experts here. Thanks/

The correct answer should be ( 3 ) as chlorophyll are mainly found in the leaves. Of course there are special cases where chlorophyll are found in the stem, such as in cacti, the leaves are needle-like, so the stem took over the function of making food for the plant. In a vague question like this, we will take it as the answer is the leaf. This is what lower levels are expected to know. There are times where we can expect mistakes in assessment books, so do practice caution whenever we refer to the answer key provided by the books, especially in section B, where key words and key concepts are expected in the answers.

Tried the curry fish head at Blk 171 Yishun Coffee Shop. Loved it, cos the fish head was really fresh.