Answer:
e. Red segregated from brown in meiosis I, and straight segregated from curled in meiosis I.
Explanation:
A cross between two flies heterozygous for both genes produced an offspring with the phenotypic ratio of 9:3:3:1. This ratio is expected according to Mendel's law of independent assortment, which states that alleles of the same gene assort independently during gamete formation.
Before meiosis starts in flies, a single diploid cell duplicates its DNA, so each chromosome has 2 sister chromatids that contain the same information.
- During meiosis I, <u>the homologous chromosomes separate</u> into two daughter cells. The chromosome number is reduced by half, but each chromosome has two sister chromatids.
- During meiosis II, <u>the sister chromatids separate</u> and each daughter cell from meiosis I divides into two new daughter cells (to get the total of 4 haploid cells).
In a heterozygous fly, each homologous chromosome contains a different allele, and the sister chromatids are copies that carry the same allele. For that reason, both traits were segregated during meiosis I.
Answer:
Parathyroid hormone increases the level of calcium while calcitonin hormone decreases the level of calcium in the blood.
Explanation:
Parathyroid hormone is a type of harmone which is responsible for balancing calcium in our body. When the calcium level lowers in our body, parathyroid hormone is secreted and calcium is absorbed from the bones and fullfilled the requirement of the body. If the tumor secreted calcitonin hormone instead of parathyroid hormone, the calcium level in the blood is lowered because it acts to the opposite of parathyroid hormone.
Answer:
Which substance has a high albedo? B) White Sand
Explanation:
The albedo is the amount of energy that is reflected by a surface. It is determined by the refletivity of that surface. Albedo can range from 0 (no reflection) to a value of 1 (100% reflection). Generally, dark surfaces have a low albedo and light surfaces have a high albedo. Liquid water is considered to have a low albedo, like dark rock and rich soil.
Answer:
They can move about freely.
They can reproduce.
They can respond to internal stimulus.
Answer:
The food chain showing seven organisms can be drawn as follows:
Plants → grasshoppers → mice → frog → snakes→ eagles → decomposers
The plants are the primary source of food in a food chain or a food web. The animals which feed on plants will be termed as herbivores or primary consumers like the grasshopper. The organisms feeding on primary consumers will be the secondary consumers like mice.
An energy pyramid for three of the organisms can be shown as follows:
mice (10 kilocalories)
↑
Grasshoppers (100 kilocalories)
↑
Plants ( 1000 kilocalories)
As the energy pyramid shows, only about 10% of the energy travels from one trophic level to another.
Explanation: