Describe the process of crossing over during prophase i and explain how genetic recombination occurs.

Which class of organisms gather their energy directly from the sun?

Gekata [30.6K]

Answer:

they are called autotrophs...

Explanation:

Autotrophs, which also called producers are the organisms which are able to produce the more complex substances like proteins fats and carbohydrates from what is around them (the sun and also carbon dioxide and water...)

HOPE THIS HELPS!!

5 0

3 years ago

Read 2 more answers

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant

Ivenika [448]

Answer and Explanation:

Available data:

Comb shape is determined by genes at two loci (R, r and P, p).

The walnut comb genotype is R_P_.

The rose comb genotype is R_pp.

The pea comb genotype is rrP_.

The single genotype is rrpp.

a. Walnut crossed with single produces 1 walnut, 1 rose, 1 pea, and 1 single offspring:

Parental) RrPp x rrpp

Gametes) RP Rp rP rp rp rp rp rp

Punnet Square) RP Rp rP rp

rp RrPp Rrpp rrPp rrpp

rp RrPp Rrpp rrPp rrpp

F1 phenotype: 25% walnut, 25% rose, 25% pea, and 25% single.

F1 genotype: 4/16 RrPp, 1/16 Rrpp, 4/16 rrPp, 4/16 rrpp.

b. Rose crossed with pea produces 20 walnut offspring.

Parental) RRpp x rrPP

Gametes) Rp Rp Rp Rp rP rP rP rP

Punnet Square) Rp Rp Rp Rp

rP RrPp RrPp RrPp RrPp

F1 phenotype: 100% walnut.

F1 genotype: 16/16 RrPp.

c. Pea crossed with single produces 1 single offspring.

This is not possible, because the pea genotype involves at least one dominant allele P. There are two possible crosses: rrPp x rrpp, which must produce half of the progeny pea and the other half single, or rrPP x rrpp which produce a whole pea progeny with no single offspring.

Parental) rrPp x rrpp

Gametes) rP rp rP rp rp rp rp rp

Punnet Square) rP rp rP rp

rp rrPp rrpp rrPp rrpp

rp rrPp rrpp rrPp rrpp

F1 phenotype: 50% pea, and 50% single.

F1 genotype: 8/16 rrPp, 8/16 rrpp.

d. Rose crossed with pea produces 2 walnut, 1 single, and 1 pea offspring.

This is not possible, because having one of the parents with a rose phenotype involves at least one R allele, which means that there must be rose phenotype in the progeny.

Parental) Rrpp x rrPp

Gametes) Rp Rp rp rp rP rP rp rp

Punnet Square) Rp Rp rp rp

rP RrPp RrPp rrPp rrPp

rP RrPp RrPp rrPp rrPp

rp Rrpp Rrpp rrpp rrpp

rp Rrpp Rrpp rrpp rrpp

F1 phenotype: 25% walnut, 25% rose, 25% pea, and 25% single.

F1 genotype: 4/16 RrPp, 1/16 Rrpp, 4/16 rrPp, 4/16 rrpp.

e. Rose crossed with single produces 31 rose offspring.

Parental) RRpp x rrpp

Gametes) Rp Rp Rp Rp rp rp rp rp

Punnet Square) Rp Rp Rp Rp

rp Rrpp Rrpp Rrpp Rrpp

F1 phenotype: 100% rose (31 individuals equal 100% of the progeny).

F1 genotype: 16/16 Rrpp.

f. Rose crossed with single produces 10 rose and 11 single offspring.

Parental) Rrpp x rrpp

Gametes) Rp Rp rp rp rP rP rp rp

Punnet Square) Rp Rp rp rp

rp Rrpp Rrpp rrpp rrpp

F1 phenotype: 50% rose, 50% single.

F1 genotype: 8/16 Rrpp, 8/16 rrpp.

3 0

3 years ago

Cells will usually divide if they receive the proper signal at a checkpoint in which phase of the cell cycle? see concept 12.3 (

NeTakaya

The correct answer is the interphase.

The cell cycle consists of three phases: the interphase (G1, S, G2) the mitotic (M) phase, and cytokinesis. The first checkpoint of the cell cycle is G1 checkpoint which is between G1 and S phase when cell checks its size, nutrients, molecular signals, DNA integrity. The second checkpoint is G2, just before the mitotic phase, when cell checks DNA integrity and DNA replication. Those two checkpoints are the ones before division, other like M checkpoint is during the mitosis.

3 0

3 years ago

What is most likely resource to be found near the base of a volcano on earth’s surface?

drek231 [11]

Something very useful and widely used from a volcano is the Basalt fibre because it has the advantage of good combination properties. It is aplied in fire-fighting, environment protection, aviation, the arms industry, atomobile and plastics and even in the construction industry

5 0

3 years ago

The height of an area above sea level can affect climate. What is this called?

Sholpan [36]

Im pretty sure it’s depth sorry if I’m wrong...have a great day:>

5 0

3 years ago