Answer:
evolution of life on Earth
Explanation:
Life began on Earth at least 3.5 to 4 billion years ago, and it has been evolving ever since. At first, all living things on Earth were simple, single-celled organisms. Much later, the first multicellular organisms evolved, and after that, Earth's biodiversity greatly increased.
Protons electrons and newtrons
<span>The protons and neutrons are located in the nucleus of the atom</span>
A. Shellfish will disappear first if an estuary was destroyed.
Answer:
1/8 (12.5%)
Explanation:
An autosomal recessive disease is an inherited disease in which an individual need to receive both defective alleles at the same gene <em>locus</em> to be expressed in the phenotype. In this case, both parents are carriers of the recessive mutant allele associated with the sickle cell anaemia trait, thereby both parents are heterozygous, ie., each parent has one copy of the normal allele 'H' and one copy of the defective mutant allele 'h' associated with this condition. In consequence, their first child has a 1/4 (25%) chance of having sickle-cell anaemia. Moreover, the chance of having a girl is 1/2 and the chance of having a boy is 1/2, thereby the final chance of having a girl sickle cell anaemia individual is 1/4 x 1/2 = 1/8 (12.5%).
- Parental cross for sickle cell anaemia trait = Hh x Hh >>
- F1 = 1/4 HH (normal); 1/2 Hh (normal); 1/4 hh (sickle cell anaemia) >>
- Sex proportion of sickle cell anaemia individuals = 1/8 female sickle cell anaemia individuals + 1/8 male sickle cell anaemia individuals (1/8 + 1/8 = 1/4)
The answer is A. Putting the aquarium in the dark means that
the aquatic plants will not be able to photosynthesize. The process of photosynthesis produces oxygen
as a by-product. The oxygen is used by the fishes in respiration and release
carbon dioxide. The carbon dioxide is used by the aquatic plants in photosynthesis.
