Answer:
47
Explanation:
We all know that gametes like egg cell and sperm have haploid set of chromosomes but here as per this question she has produced 2 copies of chromosome 21. For the sake of maintaining haploidy, she was supposed to have only a single copy of chromosome 21 as a result of which her egg cell was supposed to have 23 chromosomes not 24.
But, this is a case of non dis-junction. Also, in a normal sperm there are no such copies of any chromosome i.e. there is a haploid set of chromosomes. It means that sperm must be having only 23 chromosomes. So we can easily infer that when the egg cell and sperm will fuse, the zygote will have 47 chromosomes (24 from egg cell and 23 from sperm).
Answer: The correct answer is D
C Hypertonic
Explanation:
A sperm cell and an egg cell fuse to form a zygote.
The immune system is spread throughout the body and involves many types of cells, organs, proteins, and tissues. Crucially, it can distinguish our tissue from foreign tissue — self from non-self. Dead and faulty cells are also recognized and cleared away by the immune system.
If the immune system encounters a pathogen, for instance, a bacterium, virus, or parasite, it mounts a so-called immune response. Later, we will explain how this works, but first, we will introduce some of the main characters in the immune system.
Answer:
you could use mateirials that are easy to replenish, like recyled foam and plastic
Explanation: a good example is nikes crater shoe line
