bio exam 1

which 4 elements make up 96% of living matter?

• Carbon

• Hydrogen

• Nitrogen

• Oxygen

what is a covalent chemical bond

• when a valance shell electrons of two atoms are shared to fill there orbits

• water

A covalent chemical bond is one in which ____.

• outer-shell electrons of one atom are transferred to fill the inner electron shell of another atom.

  
  

• outer-shell electrons of two atoms are shared so as to satisfactorily fill their respective orbitals.

  
  

• protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms.

  
  

• electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged.

  Done

  
  

Which of the following is (are) true of natural selection?

• It requires genetic variation

  
  

• All of the above

  
  

• It involves differential reproductive success

  
  

• It results in descent with modification

  
  

Charles Darwin proposed a mechanism for descent with modification that stated that organisms of a particular species are adapted to their environment when they possess _____.

• non-heritable traits that enhance their survival and reproductive success in the local environment.

  
  

• heritable traits that decrease their survival and reproductive success in the local environment.

  
  

• heritable traits that enhance their survival and reproductive success in the local environment.

  
  

• non-heritable traits that enhance their survival in the local environment.

  
  

A group of the same species, in the same area, at the same time is a ______.

• population

  
  

• community

  
  

• ecosystem

  
  

• family

  Done

  
  

Which of these classes of biological molecules does NOT include polymers?

• lipids

• carbohydrates

• proteins

• nucleic acids

What is the difference between and aldose sugar and a ketose sugar?

• the position of the hydroxyl groups

  
  

• the number of carbons

  
  

• the position of the carbonyl group

  
  

• one is in ring form, the other is a linear chain

  
  

Which of the following is the best explanation for why vegetable oil is liquid at room temperature while animal fats are solid?

• Vegetable oil has more double bonds than animal fats.

  
  

• Vegetable oil has longer fatty-acid tails than animal fats have.

  
  

• Animal fats have no amphipathic character.

  
  

• Vegetable oil has fewer double bonds than animal fats.

  
  

Changing a single amino acid in a protein consisting of 325 amino acids would ____.

• sometimes alter the biological activity or function of the protein

  
  

• cause the tertiary structure of the protein to unfold

  
  

• always alter the primary structure of the protein and sometimes affect the proteins' biological activity

  
  

• alter the primary structure of the protein but not its tertiary structure or function