To produce eggs.
The large pinecones we typically see are female cones which house the eggs and then becomes a seed. The little cones that we don’t really notice are male cones
The longitudinal halves of a chromosome that has undergone replication are known as chromatids. They will not be called chromosomes until after they are separated during Mitosis. Mitosis distribute the chromatids to daughter cells as a cell divides. The chromosomes are initially replicated in cells undergoing Meiosis, as in preparation for the mitotic division, but then, these chromosomes are divided twice so that four daughter nuclei are produced, each having the haploid chromosome number.
Answer:
Explanation:
cystic fibrosis is an autosomal recessive disorder. When the child receives the defective gene from both of his parents, he suffers from cystic fibrosis. Because his parents are carriers. In recessive genetic disorder, the genes will be expressed when both recessive genes are present in one person. The person suffering from this disease have a lung infection and pancreatic dysfunction.
In this cystic fibrosis, genes are located in chromosome 7. The effective gene is the CFTR gene. The CFTR gene is present in the DNA and by transcription, this forms CFTR protein. This is a channel protein and transports chloride ion.
This CFTR protein transports chloride ions and it makes a balance in the cell membrane. These genes are commonly present in the epithelial cells. Outside the epithelial mucus is present to keep the cells moist.
The epithelium gets a lack of water and chloride due to the defect. Therefore cells need CFTR proteins also. This causes lung infection and pancreatic disorder.
Answer:
Plants and trees are the primary sources of food for a food chain or a food web. If the population of the primary producers reduces than it affects the whole food web. If the deciduous trees are destroyed due to a fire, there will be less food available for the primary predators. As a result, competition will begin between them and their population will decline. Due to this, the population of other organisms which fed on the primary consumers will also decline.
The lac operon, which stands for Lactose operon is known as an inducible system. It is the an operon required for the transport and metabolism of lactose some enteric bacteria (Echerichia coli for example). The Lac operon is only activated in the presence of a key molecule. The key molecule is lactose.
From the given options the following best describes the Lac operon:
D. The repressor is freed from the operator when lactose is present.
