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3 years ago

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In a plant, red flower color is incompletely dominant over yellow. What will the distribution of flowers in the F2 hybrids be if

we start out with 60 F1 hybrids?

1 answer:

BartSMP [9]3 years ago

8 0

1 red : 2 orange : 1 yellow<span> </span>

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How does the carbon cycle affect climate change and global warming on our planet? (Think about the different ways that carbon is

Lilit [14]

Answer:

Explanation:

The amount of global warming will depend on the magnitude of future emissions, which, in turn, depends on how society grows and develops. The rate of warming will also depend on how sensitive the climate is to increased atmospheric greenhouse gases.

Yet climate change also depends on an under-appreciated factor known as “carbon-cycle feedbacks”. Accounting for uncertainties in carbon-cycle feedbacks means that the world could warm much more – or a bit less – than is commonly thought.

The carbon cycle is the collection of processes that sees carbon exchanged between the atmosphere, land, ocean and the organisms they contain. “Feedbacks” refer to how these processes could change as the Earth warms and atmospheric CO2 concentrations rise.

The commonly used warming projections – those highlighted in Intergovernmental Panel on Climate Change (IPCC) assessment reports – include a single best-estimate of carbon-cycle feedbacks. But they do not account for the large uncertainties in these estimates.

These uncertainties are “one of the dominant sources” of divergence between different model projections, according to Dr Ben Booth and colleagues at the Met Office Hadley Centre.

Climate campaigners, such as Greta Thunberg, have also expressed concern that climate projections typically do not fully incorporate the potential range of carbon-cycle feedbacks.

This article explores the implications of carbon-cycle feedback uncertainties by examining a number of modelling studies conducted by scientists over the past decade. These studies give a similar central estimate of carbon-cycle feedbacks to those used in IPCC projections.

But, at the high end, the results show these feedbacks could push atmospheric concentrations of greenhouse gases much higher – meaning more warming – from the same level of emissions.

Analysis for this article shows that feedbacks could result in up to 25% more warming than in the main IPCC projections.

Importance of carbon-cycle feedback uncertainties

Today, around half of the CO2 emitted by humans remains in the atmosphere, with the remainder absorbed by the oceans and land. However, as the Earth warms this is expected to change. For example, warming reduces the amount of CO2 absorbed by surface ocean waters and the amount of carbon sequestered in soils. It can also accelerate tree death and the risk of wildfires. Thawing permafrost may release additional carbon into the atmosphere. Overall, the carbon cycle is expected to weaken as a result of climate change, leading to more emissions remaining in the atmosphere and less being absorbed by the land and oceans. All of these processes introduce uncertainty when translating future CO2 emissions into changes in atmospheric CO2 concentrations.

Changes in carbon cycle behavior as the Earth warms is an example of a climate feedback – a self-reinforcing change to the Earth’s temperature from a secondary factor. Not all of these feedbacks will necessarily act to increase temperature, however. CO2 fertilisation effects can lead to additional vegetation growth, sequestering more carbon. Nitrogen cycle changes can also enhance land uptake of carbon. Dynamic vegetation changes in response to a warming climate – which account for potential vegetation shifts as regional climate change – also have important, but uncertain effects on the carbon cycle.

6 0

3 years ago

Which celestial body impacts tides the most

kiruha [24]

Answer:

the sun is almost 390 times farther away from the Earth than is the moon, its high mass still affects the tides. Because the Earth’s surface is not uniform , tides do not follow the same patterns in all places.

Explanation:

5 0

3 years ago

Read 2 more answers

Both Duchenne muscular dystrophy and color blindness are caused by recessive alleles. DMD, unlike color blindness, nearly always

Ronch [10]

Answer: Although both are X-linked recessive conditions, and therefore more likely in males, with the single X-chromosome. The recessive allele in colour blindness occurs at a higher frequency in the population and is a mild condition. Thus colour blindness does occur to a lesser extent in females because it needs the double recessive condition. DMD is a severe, disabling condition with a limited lifespan, and recessive allele frequency much lower, so the double recessive condition in females is very rare.

Explanation: DMD is an X-linked recessive, “nearly always in males” suggest that it also occurs due to a new mutation or some rare condition e.g. double recessive from an affected father and carrier mother, or inactivation of the normal gene in a heterozygote. It is also found that the defective allele is not completely recessive and that female carriers may exhibit mild to moderate effects.

colour blindness is polygenic, although the genes are all X-linked. It is more common in males than females. Females can carry two recessive alleles and so express the phenotype, but this is uncommon because the frequency of the recessive gene is low.

There are similarities in that both are X-linked recessives, therefore commonly expressed in males, who only have one X chromosome. The gene frequency of the colour blindness recessive is much higher than that of DMD, so the double recessive condition, which affects females, is more likely to be seen with colour blindness. In addition, DMD is a severe condition associated with disability and limited lifespan, which reduces the probability of mating between an affected male and carrier female

6 0

3 years ago

True or false?? the extinction of a species affects other species, including humans. explain your answer..

Sonbull [250]

I'm thinking true heres why lets say you have a bird and the bird eats worms.. and all the worms in the world are gone the bird will die and what ever animal ate that bird will die and what ever animal ate that bird will die and so on

my guess

4 0

4 years ago

Read 2 more answers

The wild-type color of horned beetles is black, although other colors are known. A black horned beetle from a pure-breeding stra

Kisachek [45]

One hypothesis that explains the result is : A) Two genes are involved with 12:3:1 epistasis, such that A_B_ and A_bb are black, aaB_ is brown,and aabb is green.

Explanation:

This is a case of Dominant Epistasis.
When two genes are involved and presence of dominant allele of one gene masks the effect of either allele of the second gene then the epistasis is termed as dominant epistasis.
In the given case black :brown: green ratio is approximately equal to 12:3:1.
Here presence of a dominant A allele that is responsible for the black colour masks the effect of either allele of B. Therefore A_B_ and A_bb produces black beetles
Again , absence of dominant A allows B to express itself and Brown beetles are produced thus aaB_ is brown.
When both the genes are present as recessive alleles, neither brown nor black colour is expressed and the beetles are green.Thus, aabb are green.

4 0

3 years ago