It’s D “doing 100 sit ups in 5 minutes”
Answer:
Red blood cells transport oxygen around the body. They are specialised to carry oxygen because they: contain large quantities of a protein called haemoglobin , which can bind oxygen. don't have a nucleus, so there is more room for haemoglobin.
Explanation:
<span>Only one sperm normally fuses
with an egg because if more than one sperm fuses, through a process
called polyspermy, development of the zygote usually stops.
</span>
<span>Fertilization of one egg by
two sperm is possible, but the resulting zygote is almost never viable
because such a zygote would have three sets of chromosomes instead of
the normal two. This condition, called triploidy, is usually
incompatible with life. Those rare triploid infants that do survive to
term have severe and multiple birth defects and rarely live more than a
few days. </span>
Answer:
D
Explanation:
Everything in there pollutes the environment.
