Chapter 3.1 Flashcards
CONTROL OF GENE FUNCTION AND BIOCHEMICAL ACTIVITY IN CELLS
the degree of activation of the genes and
the formation of gene products are
themselves controlled,
gene regulation
the activity levels of already formed
enzymes in the cell are controlled.
enzyme regulation
______ or regulation of gene
expression, covers the entire process from
transcription of the genetic code in the nucleus
to the formation of proteins in the cytoplasm.
gene regulation
true or false
Regulation of gene expression can occur at any
point in the pathways of transcription, RNA
processing, and translation.
TRUE
Transcription of DNA is controlled by regulatory
elements found in the ______ of a gene
Promoter
a sequence of bases (TATAAA) called the TATA Box
and a the binding site for the TATA-binding protein
basal promoter
what are the 2 transcription factors of the basal promoter?
Transcription Factor IID Complex Transcription Factor IIB
this is located farther upstream from the transcription start site
Ø contains several binding sites for positive or negative
transcription factors that can affect transcription through interactions with proteins bound to the basal promoter
the upstream promoter
regions of DNA that can bind transcription
factors
Ø can be located a great distance from the gene
they act or upstream or downstream of that
gene
Ø more than 100,000 gene enhancer sequences
in the human genome
Enhancers
insulin-like growth factor 2 (IGF2) gene
DNA methylation
The promoter systems are especially important for controlling
intracellular concentrations of amino acids, amino acid derivatives,
and intermediate substrates and products of carbohydrate, lipid, and
protein metabolism.
true or false
false. gene control systems
In addition to control of cell function by genetic regulation, cell activities are also controlled by intracellular inhibitors or activators that act directly on specific intracellular enzymes.
__________represents a second category
of mechanisms whereby cellular biochemical
functions can be controlled.
enzyme regulation
This is a negative feedback control which is responsible for controlling intracellular
concentrations of multiple amino acids, purines, pyrimidines, vitamins, and other substances. It can be competitive and non competitive. Some chemical substances have direct feedback effects to inhibit the specific enzyme systems that synthesize them.
Almost always, the synthesized product acts on the first enzyme in a sequence, rather than on the subsequent enzymes. What is this process called?
Enzyme Inhibition
Enzymes that are normally inactive often can be activated when needed. An example of this phenomenon occurs when
most of the ATP has been depleted in a cell. cAMP acts as an enzyme activator for the enzyme phosphorylase and helps control intracellular ATP concentration.
enzyme activation
genetic system controls each stage in the
development of the human, from the single-cell
fertilized ovum to the whole functioning body.
true or false
TRUE
