Answer: between the second and
third finger
The correct method of removing
a glass stopper is to grasp it between the second and third finger with the
help of the thumb. If the glass stopper is stuck, you can use the tap method by
using many gentle tap and keep on turning the flask. Another technique is to put
oil or use a flame to expose it to heat.
Both auxin and cytokinin are used to increase size of stem and fruits
Answer:
B. stomata.
Explanation:
Stomata are openings in the surface of the plant epidermis through which gases and water vapor pass. They are formed by two elongated cells whose shape is similar to bean grain or dumbbell depending on the species. These cells are called guard cells, and in their midst there is a slit called the ostiole.
The stomata make the exchanges between the external and internal environment of the plant. They regulate the size of the opening, so it is possible to increase or decrease the rate of perspiration of the plant.
Stomata are usually located at the bottom of the leaf, but in aquatic plants such as the water lily they are at the top and still in vertical growing plants on both sides.
Answer:
Explanation:
If we break down the word autotroph, auto means “self” and troph means "feeding" or nourishment. However, when we break the word heterotroph, we get hetero- meaning other, and troph meaning feeders.
This is the critical difference between these two groups. Autotrophs synthesize or make their own food whereas, heterotrophs cannot make their own food thus have to rely on others by eating or absorbing others. For example, plants are autotrophs because they can make their own food using photosynthesis, whereas, humans are heterotrophs because we have to eat others to survive.
Answer:
Most people experience increased infant mortalities at high altitudes due to the inability of the mother to provide sufficient oxygen to the developing fetus but now variation in the DNA sequence in the people that lives at higher altitudes like in Tibetans allow normal level of infant survival at high altitudes.
This variation occurred in the EPAS1 gene in the Tibetan population that is responsible for delivering oxygen more efficiently to the fetus. This nucleotide variation is also present in low landers of Beijing but natural selection selected the variant gene in Tibetan people because they require this mutated gene for their survival.
So the population passed this variant gene in next-generation, therefore, inheritance allowed the spreading of the mutated gene to the next generation therefore by natural selection and inheritance a mutated gene spread through a human population that had just begun living high in the mountains.
