A change in the sequence of bases in a DNA molecule is known as

Maru [420]

Ecologists make models to gain insight into complex phenomena such as the effects of global warming on ecosystems.

hope this helps

8 0

3 years ago

What is a positive effect that predators have on a prey population? A. They eliminate the prey population in order to maintain c

Juliette [100K]

I will have to say D) they keep the prey population low so they will be less likely to deplete resources such as food, water, and shelter... hope i helped!!

7 0

3 years ago

Read 2 more answers

Suppose two independently assorting genes are involved in the pathway that determines fruit color in squash. These genes interac

makvit [3.9K]

Answer:

100% yellow fruit color, Yyww.

Explanation:

Available data:

two independently assorting genes

the W allele codes for a dominant white phenotype

w allele codes for a colored squash

The allele Y codes for a dominant yellow phenotype

the allele y codes for a recessive green phenotype

The phenotypes from the first locus will always mask the phenotype produced by the second locus if the dominant allele (W) is present at the first locus. This masking pattern is known as dominant epistasis

Epistasis means "interruption" and refers to interactions between genes located in different loci in the same chromosome. An “epistatic gene” can alter, influence, or suppress the expression of a "hypostatic gene". When the epistatic gene is dominant, the interaction is known as "dominant epistasis".

W suppresses the expression of Y and y, this means that whenever W is present, the fruit is white. If W is not present, the fruit color can be expressed.

So, the proposed cross in the present problem occurs between a green fruited individual and yellow fruited individual, which suggests that W is absent.

Genotype for Green fruit: yyww

Genotype for purebred Yellow fruit: YYww

Cross:

Parental) YYww x yyww

Gametes) Yw Yw Yw Yw yw yw yw yw

Punnet square) Yw Yw Yw Yw

yw Yyww Yyww Yyww Yyww

F1) 100% Yellow fruited plants, Yyww

As these two genes assort independently, we can also represent the cross for each gene by separate, like this:

For w gene:

Parental) ww x ww

Gametes) w w w w

Punnet square) w w

w ww ww

F1) 4/4 or 100% colored-fruits

For Y gene:

Parental) YY x yy

Gametes) Y Y y y

Punnet square) Y Y

y Yy Yy

F1) 4/4 or 100% yellow fruits, Yy.

3 0

3 years ago

If a nucleotide lacking a hydroxyl group at the 3' end were added to a pcr reaction, what would be the outcome?

Verdich [7]

The correct answer is b. no additional nucleotides would be added to a growing strand containing that nucleotide.

Nucleotides without a 3’hydroxy group are called dideoxynucleotides (ddNTD). Dideoxynucleotides are inhibitors of DNA polymerase because after being added in PCR reaction no further nucleotides can be added as no phosphodiester bond can be created (usually 3' hydroxyl group of the previous nucleotide attaches to 5' phosphate of the current nucleotide).

6 0

3 years ago

The xylem generally transports _____, whereas the phloem transports _____.

kenny6666 [7]

The answers are "water and mineral ions" and "amino acids and sucrose" respectively.

For the xylem, it usually transports water and mineral ions that are absorbed from the root hair cells up to the leaves, where photosynthesis take place. Water is one of the necessary substance for photosynthesis to take place, while different mineral ions can help the plant by for example Magnesium ions can help produce chloroplast.

While phloem transports amino acid and sucrose from the location of production (eg. Leaves by photosynthesis) to the place where it is used or stored. Plant needs these substances to generate energy for activities such as growth by for example cellular respiration. This process is called translocation.

Both of these tubes help transport substances in the plant, in order to keep the plant alive.

3 0

3 years ago