Answer: The following molecules would not require carrier transporters: a) carbon dioxide c) progesterone The following molecules would require carrier transporters: b) fructose d) arganine e) adenosine diphosphate Polar molecules and large ions dissolved in water cannot diffuse freely across the plasma membrane due to the hydrophobic nature of the fatty acid tails of the phospholipids that make up the lipid bilayer. Only small, non-polar molecules, such as oxygen and carbon dioxide, can diffuse easily across the membrane. Hence, no nonpolar molecules are transported by proteins in the form of transmembrane channels. These channels are gated, meaning that they open and close, and thus deregulate the flow of ions or small polar molecules across membranes, sometimes against the osmotic gradient. Larger molecules are transported by transmembrane carrier proteins, such as permeases, that change their conformation as the molecules are carried across (e.g. glucose or amino acids). Non-polar molecules, such as retinol or lipids, are poorly soluble in water. They are transported through aqueous compartments of cells or through extracellular space by water-soluble carriers (e.g. retinol binding protein). ADP/ATP translocases, also known as adenine nucleotide translocases (ANT) and ADP/ATP carrier proteins (AAC), are transporter proteins that enable the exchange of cytosolic adenosine diphosphate(ADP) and mitochondrial adenosine triphosphate (ATP) across the inner mitochondrial membrane. Solution Answer: The following molecules would not require carrier transporters: a) carbon dioxide c) progesterone The following molecules would require carrier transporters: b) fructose d) arganine e) adenosine diphosphate Polar molecules and large ions dissolved in water cannot diffuse freely across the plasma membrane due to the hydrophobic nature of the fatty acid tails of the phospholipids that make up the lipid bilayer. Only small, non-polar molecules, such as oxygen and carbon dioxide, can diffuse easily across the membrane. Hence, no nonpolar molecules are transported by proteins in the form of transmembrane channels. These channels are gated, meaning that they open and close, and thus deregulate the flow of ions or small polar molecules across membranes, sometimes against the osmotic gradient. Larger molecules are transported by transmembrane carrier proteins, such as permeases, that change their conformation as the molecules are carried across (e.g. glucose or amino acids). Non-polar molecules, such as retinol or lipids, are poorly soluble in water. They are transported through aqueous compartments of cells or through extracellular space by water-soluble carriers (e.g. retinol binding protein). ADP/ATP translocases, also known as adenine nucleotide translocases (ANT) and ADP/ATP carrier proteins (AAC), are transporter proteins that enable the exchange of cytosolic adenosine diphosphate(ADP) and mitochondrial adenosine triphosphate (ATP) across the inner mitoc.

1. Answer:
The following molecules would not require carrier transporters:
a) carbon dioxide
c) progesterone
The following molecules would require carrier transporters:
b) fructose
d) arganine
e) adenosine diphosphate
Polar molecules and large ions dissolved in water cannot diffuse freely across the plasma
membrane due to the hydrophobic nature of the fatty acid tails of the phospholipids that make up
the lipid bilayer. Only small, non-polar molecules, such as oxygen and carbon dioxide, can
diffuse easily across the membrane. Hence, no nonpolar molecules are transported by proteins in
the form of transmembrane channels. These channels are gated, meaning that they open and
close, and thus deregulate the flow of ions or small polar molecules across membranes,
sometimes against the osmotic gradient. Larger molecules are transported by transmembrane
carrier proteins, such as permeases, that change their conformation as the molecules are carried
across (e.g. glucose or amino acids). Non-polar molecules, such as retinol or lipids, are poorly
soluble in water. They are transported through aqueous compartments of cells or through
extracellular space by water-soluble carriers (e.g. retinol binding protein).
ADP/ATP translocases, also known as adenine nucleotide translocases (ANT) and ADP/ATP
carrier proteins (AAC), are transporter proteins that enable the exchange of cytosolic adenosine
diphosphate(ADP) and mitochondrial adenosine triphosphate (ATP) across the inner
mitochondrial membrane.
Solution
Answer:
The following molecules would not require carrier transporters:
a) carbon dioxide
c) progesterone
The following molecules would require carrier transporters:
b) fructose
d) arganine
e) adenosine diphosphate
Polar molecules and large ions dissolved in water cannot diffuse freely across the plasma

2. membrane due to the hydrophobic nature of the fatty acid tails of the phospholipids that make up
the lipid bilayer. Only small, non-polar molecules, such as oxygen and carbon dioxide, can
diffuse easily across the membrane. Hence, no nonpolar molecules are transported by proteins in
the form of transmembrane channels. These channels are gated, meaning that they open and
close, and thus deregulate the flow of ions or small polar molecules across membranes,
sometimes against the osmotic gradient. Larger molecules are transported by transmembrane
carrier proteins, such as permeases, that change their conformation as the molecules are carried
across (e.g. glucose or amino acids). Non-polar molecules, such as retinol or lipids, are poorly
soluble in water. They are transported through aqueous compartments of cells or through
extracellular space by water-soluble carriers (e.g. retinol binding protein).
ADP/ATP translocases, also known as adenine nucleotide translocases (ANT) and ADP/ATP
carrier proteins (AAC), are transporter proteins that enable the exchange of cytosolic adenosine
diphosphate(ADP) and mitochondrial adenosine triphosphate (ATP) across the inner
mitochondrial membrane.