Answer:
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles, and the presence of mutagens can all impact which of an animal's genes are expressed, which ultimately affects the animal's phenotype.
Explanation:
Modified nucleotides perform a large number of functions
Answer:
4. Variations that help with survival will be passed on to future generations and will rapidly change the whole population.
Explanation:
Variations that help with survival MAY be passed on to future generations, depending on how much pressure that variation relieves. Change may not be rapid, depending on how fecund the species is. Also, it will not change the whole population, only future offspring. The current offspring won't all have the new variation.
Protection for the head is needed in cases of direct collision sports like hockey and football. Collisions with another player or the turf may result in a concussion, thus all the helmets must possess NOCSAE certifications.
The helmet should fit comfortably around all the segments of the player's head, there should be no gaps between the head and pads. It should cover the base of the skull, the pads positioned at the back of the neck should be comfortable, and at the same time should not be uncomfortable.
The helmet should not come down over the eyes, the front edge of the helmet should be 3/4 inch or of two finger widths above the eyebrows.