A) Grassland: Most & Tundra: Least - This answer is incorrect, because grassland biomes are definitely not known for their high plant diversity. As one could imagine, the primary plant found here is grass (and large shrubs.)
B) Rain Forest: Most & Taiga: Least - While this answer is pretty close, a taiga biome does not hold the least amount of plant diversity.
C) Rain Forest: Most & Tundra: Least
D)Temperate Forest: Most & Taiga: Least: As mentioned in B, Taigas do not hold the least amount of plant diversity.
ANSWER:
C) Rain Forest: Most & Tundra: Least
The nuclear envelope, also known as the nuclear membrane, [a] is made up of two lipid bilayer membranes which in eukaryotic cells surrounds the nucleus, which encases the genetic material. The nuclear envelope consists of two lipid bilayer membranes, an inner nuclear membrane, and an outer nuclear membrane. The space between the membranes is called the perinuclear space.
Sperm cell (gamete) in humans = 23
Zygote in monkeys = 48
Zygote in humans = 46
Egg cell (gamete) in monkeys = 24
28. <u>Answer</u>: All mutations do not affect the organisms due to the following reasons:-
1. The DNA consists of both coding and non coding regions. The coding regions are known as exons and non coding regions are called as introns. The <em>non coding regions </em>do not make up the protein. Thus, if the mutations occur in non coding regions they do not affect the organism.
2. There are some mutations that result in the change of the codon but the new codon formed codes for the same amino as the previous one. This is possible because of the degeneracy of genetic code. For eg, AAA codes for lysine, however if the mutation changes this code to AAU then this also codes for lysine. Such mutations are called as <em>silent</em> mutations.
3. There are some mutations which result in the change in amino acid however the new amino acid formed is similar to the previous one in its properties for e.g leucine and isoleucine. Such mutations are called as <em>neutral</em> mutations and they do not affect the organism
29. <u>Answer</u>: 1. The process of mitosis results in the formation of <em>two diploid cells</em> whereas meiosis results in the formation of <em>4 haploid cells.</em>
2. The process of mitosis takes place to produce copies of the <em>body cells </em>whereas the process of meiosis takes place to produce the <em>gametes</em>.
<u>Explanation</u>:-
- <u>Mitosis</u> is a process in which a cell undergoes a single round of division to produce two identical copies of itself . It occurs in 4 phases Prophase, metaphase, anaphase and telophase. This process occurs in the body cells.
- <u>Meiosis</u> is a process in which a cell undergoes two rounds of cell division to produce 4 copies of haploid cells from a single diploid cell. This process takes place for the formation of gametes.
29. <u>Answer</u>:
<em>Pros</em>
1. Genetic engineering helps us to tackle several diseases. There are many diseases which are caused due to genetic mutations. Genetic engineering helps us to rectify these mutations and hence combat such diseases.
2. Genetic engineering helps us to produce new foods which can withstand adverse conditions such as high/low temperatures, low rainfall, are disease and pest resistant etc. This, genetic engineering helps to significantly improve crop production.
<em>Cons</em>
1. Genetic engineering leads to a decrease in genetic diversity.
2. It can lead to a decrease in the nutritional value of food as genetic engineering often causes an accelerated growth of animals and hence, the nutritional valie of poultry foods is compromised.
Answer:
D.) If the homozygous tall plant (TT) crosses with a homozygous short plant (tt), then all the F1 plants become heterozygous tall plants (Tt).
Explanation:
Homozygous indicates that the alleles in the genotype are the same. Therefore, the genotype for homozygous tall plants is (TT) and the genotype for homozygous short plants is (tt).
After performing a cross, we know that all of the children will have the heterozygous genotype (Tt).
