Answer:
Male gametes / microspores are produced in pollen cones and develop into pollen grains. Some gymnosperm species have male and female cones on the same tree, while others have separate male or female cone producing trees. ... Fertilization in gymnosperms occurs when pollen grains contact the female ovule and germinate. I hope dis helps :3
Answer:
cells are the innermost source of energy in all organisms. please give me brailiest
Answer:
by testcrossing with a homozygous recessive partner
Explanation:
<u>If a pet cockroach exists whose zygosity is unknown, this can be determined by a test cross. A test cross involves crossing an organisms whose zygosity is unknown with a partner that is homozygous recessive for the same trait.</u>
Let us assume that brown body is represented by the allele B, the dominant allele. The homozygous recessive version would be bb.
The genotype of a brown cockroach whose zygosity is not known can be denoted as B_, where '_' can be a 'B' or a 'b'.
When B_ is crossed with bb:
B_ x bb
Progeny
2 Bb
2 _b
The phenotype of Bb would be brown (since B is dominant over b) while the phenotype of _b would depend on the zygosity level of the cockroach.
If the unknown genotype is BB, then _b becomes Bb and the phenotype will be a brown body. This means that all the progeny will appear brown. (<em>see the first attached image for the Punnet's square</em>)
In other word, if the unknown genotype is bb, then _b becomes bb and the phenotype will be a alternate color (non-brown) body. This means that 50% of the progeny will appear brown while the remaining 50% will be in the alternate color. (<em>attached</em>
Dogs, cats, ferrets, seals, elephants, mustelids and bears own the "Zonary" placentae.
Polar covalent bonds.
.........
:)