1. When you cut an onion, you release their liquidy contents and previously separated enzymes meet the sulfur-rich amino acids and form unstable sulfenic acids, which then rearrange into a chemical known as syn-propanethial-S-oxide.2. Why are onions such jerks sometimes? Well, it actually comes down to some pretty fascinating biochemistry.3. It turns out that onions are particularly good at absorbing sulfur, which they use in a number of amino acids.4. The sneaky chemical is volatile, meaning it easily vaporizes, and causes a burning sensation when it floats up from the cutting board and comes in contact with your eyeballs.

he sentences given in this question, when properly sequenced, form a coherent paragraph. Decide on the proper order for the sentences and write this sequence as your answer.1. When you cut an onion, you release their liquidy contents and previously separated enzymes meet the sulfur-rich amino acids and form unstable sulfenic acids, which then rearrange into a chemical known as syn-propanethial-S-oxide.2. Why are onions such jerks sometimes? Well, it actually comes down to some pretty fascinating biochemistry.3. It turns out that onions are particularly good at absorbing sulfur, which they use in a number of amino acids.4. The sneaky chemical is volatile, meaning it easily vaporizes, and causes a burning sensation when it floats up from the cutting board and comes in contact with your eyeballs.

However, onions are perhaps best known for their ability to induce tears when chopped. When cut, onions release an irritant called______ which stimulates our eyes’ lachrymal glands so they release tear

Onion peels contain high levels of flavonoids like Quercetin, which have high antioxidant properties. These antioxidants help neutralize free radicals in the body, reducing oxidative stress and lowering the risk of chronic diseases such as heart disease and cancer.

A student prepared some onion cells. The student viewed the onion cells using a light microscope. This is the method used. 1. Cut an onion into pieces using a sharp knife. 2. Peel off a thin layer of onion epidermis from one piece of onion. 3. Place the onion epidermis onto a microscope slide in a single flat layer. 4. Add three drops of iodine solution. 5. Slowly lower a cover slip at an angle onto the onion epidermis. 6. Place the slide on the stage of the microscope. 4. Page 6 of 16Sugars absorbed via active transport would show a decrease in aborption rate where there is no respiration occuring as it needs energy to carry out active transport and from the table we can see that the sugars glucose and galactose both significantly decreased whichi informs us that those two sugards can be absorbed by active transportBecause every single sugar got absorbed which informs us that some form of diffusionhas taken place(a) The table below shows a risk assessment for this experiment. Complete the table.HazardRiskPlan to minimise risk Iodine solution is an irritant May cause allergic reaction or skin rashSharp knife(2) (b) Give a reason for each of the following steps in the method. A thin layer of onion epidermis is used. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Iodine solution is added to the onion epidermis. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ The cover slip is lowered onto the onion epidermis at an angle. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (3) Page 7 of 16Figure 1 shows what the student saw under the microscope at a magnification of ×400. Figure 1 (c) The length of cell Z in Figure 1 is 4.8 cm. Calculate the real length of cell Z. Give your answer in micrometres (μm). ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Real length of cell Z = _______________μm (5) Page 8 of 16Figure 2 shows the student’s drawing of Figure 1. Figure 2 (d) Give two ways the student could improve the drawing in Figure 2. 1 _________________________________________________________________ ___________________________________________________________________ 2 _________________________________________________________________ ___________________________________________________________________ (2) (e) Onion cells can be seen using an electron microscope. Give two ways onion cells would look different when seen using an electron microscope. 1 _________________________________________________________________ ___________________________________________________________________ 2 _________________________________________________________________ ___________________________________________________________________ (2) (Total 14 marks)

In onion & Garlic, New plants are produced fromSelect an answerAbulbsBtubesClead budsDsubaerial stems