Tutor profile: Julia L.
Subject: Natural Sciences
How do plants grow if humans don't plant the seeds?
Plants have been on Earth for a long time, and through the decades have learned tricks in order to stick around! Flowers began to develop, which the bright colors attracted animals and bugs, who would accidentally pick up the seeds or pollen and spread them to other areas. Plants grow seeds that are designed to travel. Some look like propellor blades and fly through the air when a gust of wind comes by. Other seeds have burrs on them (think of velcro) that stick to animals and fall off in different places. Some plants grow fruits that animals eat, when the animal goes to the bathroom later, a seed is also planted! There are many ways for plants to spread their seeds other than humans sticking them into the ground. Plants have been around longer than we have after all.
Subject: Health and Medicine
Is fruit juice as good for you as whole fruit?
While fruit juice and whole fruit both contain vitamins and minerals, whole fruit is a better choice. The main difference between the two is fiber. Fiber is something found in fruits, vegetables, and grains that is not digested by our systems. When we eat food, our body takes sugar (carbohydrates) and puts the sugar into our blood to use for energy. If you eat a high amount of sugar, it will go into your blood stream and put stress on your body to allocate the high amount of sugar to different areas of the body. If you eat foods that contain fiber, the sugar found in food will still get into your blood, but at a slower rate- giving your body time to allocate the sugar to different areas of the body at a steady rate, and not put stress on the body. When drinking fruit juice, it contains all the sugar that fruit does (maybe more), and has no fiber. Meaning that your body will receive a large amount of sugar at once, and no fiber to help slow down the release of sugar. Eating the whole fruit contains all the vitamins, minerals, sugars, AND fiber that helps with slowing the release of sugar into your system. While fruit juice is not the best choice, it can still be consumed in moderation, and adding in whole fruits as well!
Subject: Food Science
What causes some types of fat to be solid at room temperature and for others to be liquid?
There are two main types of fats- saturated and unsaturated. Saturated fats are solid at room temperature, while unsaturated fats are liquid at room temperature. The molecular structure of saturated fats is mostly a flat chain. The molecular structure of unsaturated fats have a kink in them, causing the chain to not lay flat. Think about a common saturated fat, butter. At room temperature butter is solid. Think of having hundreds of flat sticks all laid flat in a box, see how you easily stack them ontop of one another to create a block shape. The saturated fat molecules in butter act like flat sticks and can easily hold a solid shape at room temperature. Now think of a common unsaturated fat, olive oil. At room temperature olive oil is liquid. Think of having hundreds of bent sticks in a box and see how easily it is to stack them on top of one another to create a block shape..Not so easy! The unsaturated kinked fat molecules in olive oil do not sit perfectly ontop of each other, causing them to not hold a shape at room temperature- this is why olive oil is liquid at room temperature.
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