Bio 201 Exam 1 (Chapters 1-3)
Question and answers correctly
solved 2025/2026
What are the three domains of life? - correct answer ✔Bacteria, Archaea, Eukarya
Describe the Bacteria domain - correct answer ✔Unicellular
Adaptation to all environments
No membrane bound organelles
Describe the Archaea domain - correct answer ✔Unicellular
Adaptations to extreme environments
No membrane bound organelles
Describe the Eukarya domain - correct answer ✔Uni or multicellular
Membrane bound organelles
Nucleus
Very complex
The four most important elements of life are? - correct answer ✔Carbon- ¹²₆C
Hydrogen- ¹₁H
Nitrogen- ¹⁴₇N
, Oxygen- ¹⁶₈O
Based on the arrangement of electrons, how many covalent bonds can Carbon form? - correct answer
✔4
Based on the arrangement of electrons, how many covalent bonds can Hydrogen form? - correct
answer ✔1
Based on the arrangement of electrons, how many covalent bonds can Nitrogen form? - correct answer
✔3
Based on the arrangement of electrons, how many covalent bonds can Oxygen form? - correct answer
✔2
Why is it so important to life that water is an excellent solvent? - correct answer ✔Water is considered
the universal solvent, it can dissolve a great number of substances, more than any other liquid. With out
water, every living organism would die.
What would happen if solid water was denser than liquid water? - correct answer ✔The liquid water
would freeze turning into ice, the solid water would then sink because it would be less dense than the
liquid water, eventually killing all life forms that live in water.
Substance #1 has a pH value of 4.2 while substance #2 has a pH value of 5.2. Which substance is more
acidic and by a factor of how much? - correct answer ✔Substance #1 is more acidic. Thus substance #1
is 10 times more acidic than substance #2.
What is the purpose of buffers? - correct answer ✔A buffer is a chemical or combination of chemicals
that keeps pH within normal limits.
Question and answers correctly
solved 2025/2026
What are the three domains of life? - correct answer ✔Bacteria, Archaea, Eukarya
Describe the Bacteria domain - correct answer ✔Unicellular
Adaptation to all environments
No membrane bound organelles
Describe the Archaea domain - correct answer ✔Unicellular
Adaptations to extreme environments
No membrane bound organelles
Describe the Eukarya domain - correct answer ✔Uni or multicellular
Membrane bound organelles
Nucleus
Very complex
The four most important elements of life are? - correct answer ✔Carbon- ¹²₆C
Hydrogen- ¹₁H
Nitrogen- ¹⁴₇N
, Oxygen- ¹⁶₈O
Based on the arrangement of electrons, how many covalent bonds can Carbon form? - correct answer
✔4
Based on the arrangement of electrons, how many covalent bonds can Hydrogen form? - correct
answer ✔1
Based on the arrangement of electrons, how many covalent bonds can Nitrogen form? - correct answer
✔3
Based on the arrangement of electrons, how many covalent bonds can Oxygen form? - correct answer
✔2
Why is it so important to life that water is an excellent solvent? - correct answer ✔Water is considered
the universal solvent, it can dissolve a great number of substances, more than any other liquid. With out
water, every living organism would die.
What would happen if solid water was denser than liquid water? - correct answer ✔The liquid water
would freeze turning into ice, the solid water would then sink because it would be less dense than the
liquid water, eventually killing all life forms that live in water.
Substance #1 has a pH value of 4.2 while substance #2 has a pH value of 5.2. Which substance is more
acidic and by a factor of how much? - correct answer ✔Substance #1 is more acidic. Thus substance #1
is 10 times more acidic than substance #2.
What is the purpose of buffers? - correct answer ✔A buffer is a chemical or combination of chemicals
that keeps pH within normal limits.
