Answer: Only options A, B, C and D are true statements
A) One sperm fuses with an egg while the other sperm fuses with the polar nuclei.
B) It results in the formation of a diploid embryo and triploid endosperm.
C) Both sperms involved in double fertilization form within the same pollen tube.
- The diploid nucleus resulting from the second fertilization undergoes meiosis to form the endosperm.
Explanation:
Double fertilization is a process that occurs in only flowering plants. It involves the following:
- A pollen grain produces TWO male gametes
- one male gamete fertilize the egg to form a zygote that is DIPLOID (with two basic sets of chromosomes)
- the second male gamete fuses with another cell named POLAR NUCLEI, to form endosperm (the food storing tissue) in the seed. The endosperm formed is TRIPLOID ( it has three sets of chromosomes), having undergone reductive division - meiosis
Thus, the options A, B, C and D are true statements
Answer:
Option A, cribra orbitalia in eye orbits.
Explanation:
Cribra orbitalia (CO) in eye orbits is caused by the iron deficiency of anemia which leads to weakening of bones of eye sockets by making it porous. It is also known as porotic hyperostosis of the orbital roof. Some of the common causes of this disease as claimed by researchers are malnutrition, insufficient diet and parasite.
Dietary deficiencies lowers the level of iron and other vitamins such as B9 and B12) thereby causing anemia known as megaloblastic anemia.
Hence option A is correct
Our earth is in constant nonstop motion
Answer:
True, because yes they do have blood vessels, and ofc bones grow, they do as our body grows more! (◍•ᴗ•◍)
