Structure and Composition of the body Flashcards
(48 cards)
At the molecular level, the body consists of four macromolecules
What are they?
- Proteins
- Carbohydrates
- Lipids
- Nucleic Acids
Proteins are a polymer of what?
Amino Acids
the body utilizes some 20 different amino acids from which it synthesizes proteins.
What are the roles of protein in the body?
Proteins have a variety of roles in the body
- They act as receptors for hormones and neurotransmitters
- They act as enzymes
- They act as carrier molecules transporting material across cell membranes.
Carbohydrates exist in many forms
What are they?
Monosaccharides (e.g. glucose)
OR
Polysaccharides which are polymers of many monosaccharides (e.g. Glycogen)
What is the role of carbohydrates?
The primary role of carbohydrates is to act as an energy source for the many reactions occurring within the body.
Some organs (e.g. Brain)have an absolute dependence on glucose as a source of energy .
What is the job of Polysaccharides?
Polysaccharides function as an energy store such as glycogen which can be broken down into monomers (glucose) to provide a source of energy.
Draw:
- The typical structure of an amino acid,
- How it forms a peptide bond to form proteins
THRIVE IN PHYSIOLOGY PAGE 2 FIGURE 1.1
Draw the structure of glucose
THRIVE IN PHYSIOLOGY PAGE 2 FIGURE 1.2
Glycoproteins and Glycolipids are a combination of what?
1) Carbohydrates combining with protein
2) Carbohydrates combining with lipids
Do carbohydrates contribute to the structure of DNA and RNA?
YES
A final role for one group of carbohydrates is to contribute to the structure of DNA and RNA
What is the function of Lipids?
Lipids are water-insoluble compounds, unlike proteins and carbohydrates, which perform a variety of roles in the body.
Lipids are an important component in the formation of cell membranes
- They act as an energy source
- And some of them act as hormones (e.g. steroids and the prostaglandins.)
What are nucleic acids?
Nucleic acids (DNA and RNA) are the principal components in the storage and transfer of genetic information.
How is DNA formed?
DNA is formed from a sugar molecule (Deoxyribose sugar) linked to a variety of bases ( Thymine, Cytosine, Guanine and Adenine.)
How is a Nucleoside and a Nucleotide formed?
A molecule of sugar combined with a base produces a structure called a Nucleoside.
When this becomes linked to a phosphate group it forms a nucleotide.
What is DNA and RNA a polymer of?
Nucleotides
How is RNA different to DNA?
- RNA is composed of a ribose sugar instead of a deoxyribose sugar
- RNA also has uracil which replaces thymine as a base.
How is DNA stored in the form of chromosomes?
DNA is stored, in conjunction with histone proteins, in the nucleus of the cell in the form of chromosomes.
The structure of DNA?
THRIVE IN PHYSIOLOGY page 3 Fig 1.3
What is the structure of an animal cell?
THRIVE IN PHYSIOLOGY page 4 Fig 1.4
What are cells?
Cells are the basic building blocks of the human body.
What is a plasma membrane?
All cells are bound by a plasma membrane. The membrane consists of lipids and proteins, and works to regulate the passage of material into and out of the cell.
Some substances can move across the membrane by simple diffusion (depending on their size and lipid solubility), whilst others need specialized energy consuming transport molecules.
What is the structure and components of the plasma membrane?
THRIVE IN PHYSIOLOGY page 4 Fig 1.5
What is the function of the nucleus?
The nucleus lies within the cytoplasm of the cell, and at its boundary is the nuclear membrane.
The nucleus contains the DNA of the cell, which in conjunction with histone proteins, forms chromosomes.
What is the function of the mitochondria?
Mitochondria within the cytoplasm act as energy transducers. They do this by oxidizing glucose and fatty acids and in doing so produce Adenosine Triphosphate (ATP). ATP is the energy source which cells depend on.
The more active a cell is e.g. a muscle cell which has to contract, the greater number of mitochondria it has.
A transducer is a cell that transforms one type of input to another.