Xylem Phloem are the vascular tissues that transport the food, minerals and water within the plant. Xylem transport the water and minerals while Phloem transport food and nutrients. The movements in Xylem is unidirectional from roots to aerial parts while the movements in Phloem are bidirectional.
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)
Answer: Muscles cell contain myosin II, which is responsible for muscle contractions.
Explanation:
Myosin are motor proteins that are responsible for muscle contractions and motility processes in animals.
Myosin II is also called conventional myosin is a form of myosin found in muscles cells and are responsible for muscles contraction in animal cells. It is found in non muscles cells called stress fibers.