Describe the different types of bonds in a protein molecule. Why are the positio

ID: 60610 • Letter: D

Question

Describe the different types of bonds in a protein molecule. Why are the positions, types and strength of these bonds so important to protein function?
Explain the diversity and structure of lipids.
Describe or draw the cyclical process of dehydration synthesis and hydrolysis. Give examples using carbohydrates, lipids and proteins.
Elaborate the structure of the cell membrane. Describe or draw it. Explain why cells are so small AND the importance of selective permeability.
Describe the endomembrane system that exists inside the cell
What is the cytoskeleton? Describe the parts. Explain its importance in the cells activities.
An artificial “cell” consisting of an aqueous solution enclosed in a selectively permeable membrane is immersed in a beaker containing a different solution. The membrane is permeable to water and to the simple sugars glucose and fructose. It is impermeable to sucrose (a disaccharide). Draw and label this scenario.

Draw solid arrows to indicate the net movement of solutes into and/or out of the cell
Is the solution outside the cell isotonic, hypotonic or hypertonic
Draw a dashed arrow to show the net osmosis. (if any)
Will the artificial cell become more flaccid, more turgid or stay the same?
Eventually, will the two solutions have the same or different solute concentrations?

8)Paramecium and other protists that live in hypotonic environments have cell membranes that limit water uptake, while those living in isotonic environments have membranes that are more permeable to water. What adaptations might have evolved in protists in hypotonic habitats such as the Great Salt Lake? In habitats with changing salt concentrations?

A human pancreatic cell obtains oxygen and necessary molecules such as glucose, amino acids and cholesterol from its environment, and it releases carbon dioxide as a waste product. In response to hormonal signals, the cell secretes digestive enzymes. It also regulates ion concentrations by exchange with its environment. Based on what you know about the structure and function of cell membranes, describe how a cell accomplishes these interactions with its environment.
As a cell begins the process of dividing, its chromosomes become shorter, thicker and individually visible in an LM. Explain what is happening at the molecular level.

Explanation / Answer

Different types of bonds in a protein molecule are:

For example, the peptide bond is the back bone of proteins. The peptide bond is formed between the amino group one amino acid and carboxylic group of another amino acid by elimination of one water molecule. So, it is a very strong planar bond formed by condensation reaction.

The remaining interactions play an important role in formation of secondary, tertiary and quaternary structures.

Examples of carbohydrates, lipids and proteins:

S.no

Type

Monomer

Examples of Polymer

Carbohydrates

Sugar moieties

Glycogen and starch

Proteins

Amino acids

Enzymes and albumin

Lipids

Fatty acids

Triacylglycerol

Nucleic acids

Nucleotides

DNA and RNA

The dehydration refers to removal of water molecule from the reactants in the reaction. In this reaction one hydroxyl group from one amino acid and one hydrogen atom from another amino acid are removed and combined to from a water molecule.

For example, consider the cyclical process of dehydration synthesis of proteins:

The plasma membrane is a semipermeable membrane and can regulate the movement of substances across the membrane. The lipids and proteins that are present in the membrane are responsible for the semipermeable nature of the plasma membranes. The adjoined picture shows the structure of plasma membrane: