Photo receptors are attached to the retina and are most numerous specifically at the fovea
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)
Nitrogen has two (2) lone pairs
Clouds form when moist, warm rising air cools and expands in the atmosphere. The water vapor in the air condenses to form tiny water droplets which are the basis of clouds.
Answer:
Heterotrophs obtain chemical energy for their survival by eating plants and animals.
Explanation:
- The chemical energy that organism need comes from food. They break this food down to obtain energy.
- Depending on their source of nutrients , they are classified into: Autotrophs and Heterotrophs.
- Autotrophs use sunlight and photosynthesize to produce their own food. They are often known as producers.
- Heterotrophs are beings that can't prepare their own food and consume other organisms to obtain energy.They are also called consumers.
- Examples include: Animals, fungi,etc.
