Answer: Transcription begins when RNA polymerase binds to a promoter sequence near the beginning of a gene (directly or through helper proteins). RNA polymerase uses one of the DNA strands (the template strand) as a template to make a new, complementary RNA molecule. Transcription ends in a process called termination.
Sulfur emissions from industry combine with water in the atmosphere and form acid rain. A new factory is built very close to the lake that Josh visits often. By examining the table that shows what pH range different species can survive, Josh decides that the aquatic life will be affected by the changes in pH that the lake. Josh correctly decides that organisms that will be the most affected are
A) perch and frogs.
B) mayfly and bass.
C) snails and clams.
D) frogs and salamanders.
The correct answer is option (C) snails and clams.
Acid rain is formed when oxides of sulfur and nitrogen combine with water molecules. Industries are one of the major contributors to acid rain. pH is a measure of acidity or alkalinity in water.
A factory built close to the lake can cause acid rain which affects the pH of the lake. Any change in the pH of the lake has an effect on the organisms in it. A pH of 7 is considered to be neutral and pH values below 7 indicates acidity and pH values above 7 indicates alkalinity. Organisms have an acid tolerance level beyond which they are affected and can die. Perch has an acid tolerance of up to pH 4.5 and frogs can tolerate an acidic pH of 4.0. The acid tolerance level of Mayfly and Bass is a pH of 5.5. Salamanders can tolerate an acidic pH of 5. Whereas, Snails and Clams have a very less pH tolerance of 6. They are highly susceptible to acidic pH.
Thus, Josh correctly decides that organisms that will be the most affected are snails and clams.
Answer:
A. sexually
Explanation:
The organism has haploid gametes. Human sex cells (egg and sperm cells) contain a single set of each chromosome, making them haploid. During fertilization, the organism acquires a set of chromosomes from each parent, making it a diploid (two sets of each chromosome) zygote.
Hope this helps.
Answer:
Option A, most closely related to mammals
Explanation:
Insects like arthropods and molluscs have an open circulatory system and thus do have a distinguishable heart. Fish has two chambered heart. Reptiles have three chambered heart. Amphibians too have a three chambered heart.
All mammals and fish have four chambered heart. The right and left sides of the chambers have restricted entry and hence remain intact from each other
Hence, option A is correct
