Answer:
64
Explanation:
A codon is a group of three nucleotide sequence in a mRNA that specifies a particular amino acid acid. There are only four nucleotides composed of the four nitrogenous bases viz: Adenine, Guanine, Cytosine and Thymine/Uracil.
A codon is composed of only three of these nucleotide bases at a time. Hence, considering the number of nucleotide bases that can make up one codon and the 4 nucleotide bases, there can only be 4^3 = 64 combinations of the four nucleotides. This means that there are 64 possible codons.
The correct answer is option B
Species interactions are categorized based on their reciprocal effects (the effects that the interaction has on each species/individual involved).
1. Bees pollinate plants as they move from flower to flower collecting pollen.
This is a mutualistic relationship because the both species involved in this interaction benefit from the interaction. The bee benefits because it obtains nectar which is provided by the plant. The plant benefits because the bee carries the plants pollen to other plants, allowing the plant to reproduce.
2. Green algae grow on the backs of spider crabs living in shallow water.
This is another example of a mutualistic relationship because both species involved in this interaction benefit from the interaction. The spider crab benefits from the camouflage that the algal growth provides, while the algae benefits from the protection from predators provided by the spider crab.
3. Fleas living on skin of dogs and obtaining nutrients from dogs blood.
This is a parasitic relationship because one of the species benefits from the interaction while the other species in negatively impacted by the interaction. The flea benefits from the nutrients obtained from the dogs blood while the dog is negatively impacted by the fleas presence (loss of blood, discomfort).
4. Nitrogen-fixing bacteria obtain nutrients from host plants and use the nitrogen to supply host plants with nitrogen.
This is an example of mutualism because both species in this interaction are benefitting from the interaction. The nitrogen fixing bacteria benefit by receiving nutrients from the host plant while the host plant is benefitting from receiving nitrogen from the bacteria.
Feel free to comment and ask any additional questions.
Most of the time but not always. When it doesn't, it results in a gene mutation.
Answer:
an apple causes antibiotic resistance
Life Cycle
Mealworms that birds, reptiles, and other animals love aren’t really worms. They are the larvae of darkling beetles. There are over 20,000 different types of darkling beetles and mealworms come from the species Tenebrio molitor.
A darkling beetle experiences complete metamorphosis which means that it has four distinct stages of life. The four stages are egg, larva, pupa, and adult. The amount of time a darkling beetle spends in each stage can vary greatly due to environmental factors like temperature, humidity, food, and water.
Egg
The first stage of life is spent as an egg. The white bean-shaped egg is tiny and about the size of a speck of dust. The egg is sticky and is quickly concealed by dirt, dust, and substrate. It will take around one to four weeks for an egg to hatch and the larva to emerge.
Larva
The second stage of life lasts about eight to ten weeks and is spent as a brown larva. This is the stage where the insect is a mealworm. When first hatched, it is quite small but will grow to one to one and a half inches long.
Since it has a hard exoskeleton, the worm will need to molt and shed its hard outer shell in order to grow. Molts will occur ten to twenty times during this stage of life. A recently molted worm will be soft and white, but the exoskeleton will quickly harden.
A mealworm spends its time eating and growing in order to save up energy for the next transformation.
Pupa
During a mealworm’s last molt it will turn into a white alien-like pupa. It has no mouth or anus so does not eat. It does have leg and wing buds, but they do not function. The pupa is quite helpless and the only movement it can do is wiggle. This stage of life will last one to three weeks as the pupa transforms its organs and body into an adult.
Adult
The final stage of the insect’s life is as the darkling beetle and lasts one to three months. The beetle will be white with a soft exoskeleton. As the outer shell hardens, it will turn brown and then black. The beetle does have hard wings, but it is unable to fly.
After about one to two weeks of adult life, beetles will begin to mate and reproduce. A few days after mating, female beetles will burrow into soil or substrate and lay eggs. Darkling beetles are prolific breeders and females can lay hundreds of eggs during their adult lives.
