I think impact accretion provides thermal energy to the differentiation of different layers in a planetiesimal. Accretion is the process through which planets form as material orbiting some stars gathers together through collisions and gravitational or electrostatic attraction, eventually forming larger and larger bodies. Planetesimals are objects that forms through accretion during the early stages of planet formation. They may combine with one another to form protoplanets and eventually planets.
4: One that produces asexually and has offspring that are genetically different.
If the environment changes, many members of a certain species may die and so it becomes less and less likely for that species to produce sexually, so it will die out. Furthermore, if the asexual species produces the same traits, that species will not adapt to changes in the environment and will also die out.
Hope this helps ^^
Deforestation, pollution of fresh water
Answer:
Proportion of the F2 male with red eyes and forked bristle will be 1/4
Explanation:
forked bristles are caused by an allele (Xf) that is X linked and recessive to an allele for normal bristles (X+).
Brown eyes are caused by an allele (b) that is autosomal and recessive to an allele for red eyes (b+)
A female fly that is homozygous for normal bristles and red eyes mates with a male fly that has forked bristles and brown eyes
X+X+b+b+ x Xfbb
the F1 gives 1/2X+Xf 1/2b+b
1/2X+Y 1/2b+b
intercross of F1
Proportion of the F2 male with red eyes and forked bristle will be
forked bristle= Xfy = 1/2 and for red eyes 2/4= 1/2 = 1/2x1/2 =1/4