The year is based off of Earth’s revolution around the sun. 1 year is equal to the amount of time that it takes for Earth to revolve once around the sun.
        
                    
             
        
        
        
Answer:
The correct answer is: a.
Explanation:
- A Diploid organism possess two copies ( also called alleles) of each  autosomal gene, of which one copy of the gene is obtained from one of its parents and the other copy from its other parent.
- During the process of replication, one of the alleles of the GTPase encoding gene undergoes a mis-sense mutation.
- A Mis-sense mutation can be defined as a non-synonymous mutation in which one of the nucleotide in the sequence of the gene gets altered such that it causes a change in the amino acid encoded by the codon (triplet nucleotide message encoding for a single amino acid)  formed by the mutated nucleotide. A single amino acid change in the protein, if occurs in the functional site of the protein, can render a protein non-functional. 
- Hence, the mis-sense mutation in one of the alleles encoding for the GTPase gene causes the resulting protein produced from the mutated allele to have drastically reduced function (1%).
- A heterozygous cell is one which has one copy of the normal allele and the other copy of the mutated allele of the GTPase encoding gene.
- As one copy of the normal GTPase allele is present in such an individual, it can produce the normal GTPase protein that can assist in the process of cell growth and division.
- Hence, the phenotype(expressed character) of  the heterozygous cell will not be affected due to the mutation and it will be able to grow and divide normally.
 
        
             
        
        
        
Answer
Environmental pressures
Basically every animal adapts to pressures from their environment in different ways, causing them to have different shapes and sizes
 
        
             
        
        
        
All viruses have a capsid or head region that contains its genetic material. The capsid is made of proteins and glycoproteins.
 
        
             
        
        
        
Answer:
A
Explanation:
The dead matter from organisms such as plants and animals that die need to be recycled so the nutrients in the matter are released and used up by other organisms. This is how sustainability is achieved in ecosystems through a cyclical nature of nutrients flow. Decomposition of the dead matter is done by decomposers such as fungi and bacteria. Without them, the dead matter would accumulate while the soil would lack nutrients for plants to grow and for other bacteria to utilize for energy. This would affect the rest of the food chain/web causing the ecosystem to collapse.