Answer:
DNA can be described as the molecules which carries the genetic code for every individual. The DNA is made up of nucleotide bases which join the two strands of DNA. The sugar and phosphate form the backbone of the DNA. 
Genes are the hereditary molecules which are made up of DNA. The alleles of a gene represent which traits will be carried by an organism. 
Chromosomes are made up of genes. During reproduction, crossing over of DNA occurs and alleles of the genes assort independently due to which variations occur. 
 
        
             
        
        
        
Serine, threonine, and tyrosine are most commonly phosphorylated in eukaryotes.
 
        
             
        
        
        
Answer:
Explanation:
The main  function of the plasma membrane is to protect the cell from its surroundings. Made of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules it also regulates the movement of substances in and out of cells. Plasma membranes must be very flexible in order to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. Membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors, which then trigger intracellular responses. Some viruses, such as Human Immunodeficiency Virus (HIV), can intercept  these receptors to get into the cells, causing infections.
 
        
             
        
        
        
The answer is C. Pheromones are hormones (which are proteinous) produces by individuals of the same species and are a means to send communication signals for social interactions. They signal alarm, food and even sex. Sex pheromones are  released by females beetles into the environment to signal their availability for mating. The pheromones are picked up by receptors on the male beetles and this is how they find the females.   
 
        
                    
             
        
        
        
The more advance the community the more complex the speciess