Mice that are injected with the living R strain survive.
Answer:
b. Ebola and Lassa are both caused by viruses.
Explanation:
Ebola fever is caused by the Ebola virus which is an enveloped virus and is a member of<em> Filoviridae</em>. Ebola virus infection is 80% fatal. The incubation period for pathogen ranges from 2 to 21 days. Symptoms of the infection are fever, muscle and joint ache, stomach pain, bleeding, etc. Lassa hemorrhagic fever is caused by the Lassa virus. Infection with the Lassa virus causes fever, malfunctioning of the gastrointestinal system and bleeding.
Answer:
Ribosomes are present attached to the rough ER:
1. To easily make proteins that are required inside and outside of a cell.
2. To take up amino acids easily.
3. To make it easier for the mRNA to travel from the nucleus to the ribosomes.
Explanation:
Ribosomes are involved in the synthesis of proteins. The rough endoplasmic reticulum is attached to the nuclear envelope. Hence, this provides an easy pathway for molecules to travel between the nucleus, rough ER and endoplasmic reticulum.
During the formation of a protein, mRNA is formed and the mRNA travels to the ribosomes through the rough ER. The location of the ribosomes makes it easy to take mRNA from the nucleus and amino acids from the cytoplasm and make proteins. When a protein is made, it can be used inside the cell or can be transported to the Golgi apparatus etc.
Answer:Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population. If they are met, natural selection automatically results.
Explanation:
