True Or False: New DNA is copied from exsisting DNA.

You have learned that the fusion of egg and sperm produces a zygote. But how does the sperm reach the egg, and how does the zygo

FrozenT [24]

Answer:

Pollen grain lands on stigma

Explanation:

A) Pollen grain lands on stigma

pollen tube grows down the style
generative cell divides, forming two sperm
two sperm are discharged to them female gametophyte
sperm fuse with the egg and two polar nuclei
zygote forms and divides into a terminal cell and a basal cell
cells of embryo differentiate into three tissue types---- seed dries out and becomes dormant.

B)

During pollination, a pollen grain is transferred from an anther to a stigma. Once the pollen grain lands on a suitable stigma, it germinates and forms a pollen tube, a structure that grows down through the style to the ovary.
Once in the pollen tube, the generative cell from the pollen grain divides by mitosis, forming two sperm. The sperm travel down the pollen tube and are discharged into the female gametophyte. In a process called double fertilization, one sperm fertilizes the egg, forming the zygote; the other sperm fuses with two polar nuclei in the female gametophyte, forming a triploid (3n) nucleus. The zygote develops into the plant embryo, and the triploid nucleus divides and gives rise to the endosperm. Double fertilization prevents the waste of the plant's resources by ensuring that the nutrient-rich endosperm only develops if the egg is fertilized.
After double fertilization, the ovule starts to develop into a seed containing the plant embryo. As the embryo develops, the three tissue systems are established, and the cotyledons (seed leaves) form. The seeds of many species dry out as they mature. These dry seeds lie dormant until suitable germination conditions occur.

3 0

2 years ago

Today, you will write one to two paragraphs in which you introduce and support an opinion to the prompt:

Mashcka [7]

Answer:

Yes, future exploration to the poles important for humans.

Explanation:

This is important we need to know more about what is going on in the poles. Reason one is because we have no clue what could be living there and how it is living There in the cold places it. Second That could also help with global warming and I say this because some testing could be done to see what we could do to stop it or at least slow it down. Last but not least they can also find new animals just like how there is more animal or fishes the live in the sea. This would help us learn what is beyond what we look for. In conclusion, there is more to learn at the poles and every where else.

7 0

2 years ago

Read 2 more answers

wasp pollinating a plant in exchange for food is an example of Group of answer choices A) both a service mutualism and a habitat

masya89 [10]

The answer is biology

3 0

2 years ago

Using natural resources is considered a sustainable practice because most natural resources are in limitless supply and cannot b

Maksim231197 [3]

Explanation:

Using natural resources is cinsidered a sustainable paractice because most natural resources are in limitless supply and cannot be deprafeor depleted because natural resoures are the engery created by eco_ system which never depleted and runs continusoly to generation to generation.

HOPE U UNDERSTAND ☺☺☺☺

5 0

3 years ago

Which statement is true of recessive sex-linked traits such as color blindness ?

Korolek [52]

Answer:

colorblidness is carried on the X cromasome. since it is resessive it can be covered up. woman have 2 X cromasomes so both have to have it or she wont be color blind. men only have one X cromasome so its more likely that their just one X can have it

Explanation:

7 0

2 years ago