How do cells know which genes to transcribe?
In order for the RNA polymerase to bind to the promotor site (the first step needed for transcription) most of the time a specific Transcription Factor must bind first. Internal and external signals determine which transcription factors are present in a given cell.
How do you determine which chromosome is a gene on?
The chromosome on which the gene can be found. The first number or letter used to describe a gene’s location represents the chromosome. Chromosomes 1 through 22 (the autosomes) are designated by their chromosome number. The sex chromosomes are designated by X or Y.
What triggers gene expression?
Gene expression is influenced by numerous factors, including molecules within the cell, mutations causing dominant negative effects and haploinsufficiency, signaling molecules from surrounding cells and the environment, and epistasis. Various molecules within the cell modulate gene expression.
How does the cell know which proteins to make?
The type of RNA that contains the information for making a protein is called messenger RNA (mRNA) because it carries the information, or message, from the DNA out of the nucleus into the cytoplasm. Through the processes of transcription and translation, information from genes is used to make proteins.
Where does the translation occur in the cell?
the ribosome
Where Translation Occurs. Within all cells, the translation machinery resides within a specialized organelle called the ribosome. In eukaryotes, mature mRNA molecules must leave the nucleus and travel to the cytoplasm, where the ribosomes are located.
What does each chromosome pair determine?
Each chromosome has a distinct banding pattern, and each band is numbered to help identify a particular region of a chromosome. This method of mapping a gene to a particular band of the chromosome is called cytogenetic mapping. For example, the hemoglobin beta gene (HBB) is found on chromosome 11p15.
Where does translation take place in the?
Translation occurs in a structure called the ribosome, which is a factory for the synthesis of proteins. The ribosome has a small and a large subunit and is a complex molecule composed of several ribosomal RNA molecules and a number of proteins.
Is PP genotype or phenotype?
There are three available genotypes, PP (homozygous dominant ), Pp (heterozygous), and pp (homozygous recessive). All three have different genotypes but the first two have the same phenotype (purple) as distinct from the third (white).
How do cells know what to differentiate into?
Signals from the environment—chemicals, extracellular proteins/hormones/factors, neighboring cells, the physical environment—converge on the cell, typically activating a signaling cascade that leads to gene expression. These specific proteins change the phenotype into that of a more specialized cell.
How do cells know?
A cell’s behaviour is determined almost entirely by proteins: large molecules that the cell assembles by chaining together smaller molecules (called amino acids). Proteins carry out all the tasks that a cell needs to do, like catalyse chemical reactions, signal to other cells, or move things around within the cell.
What are chromosomes and where are they located?
Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. What is a chromosome? Chromosomes are thread-like structures located inside the nucleus of animal and plant cells.
What is the difference between a chromosome and a gene?
Chromosome = coiled DNA You have 46 chromosomes or 23 pairs in the nucleus of each body cell. 23 from mom and 23 from dad Gene = a segment of DNA that codes for a protein, which in turn codes for a trait (skin tone, eye color, etc); a gene is a stretch of DNA.
What are the two types of chromosome translocation?
In genetics, chromosome translocation is a phenomenon that results in unusual rearrangement of chromosomes. This includes balanced and unbalanced translocation, with two main types: reciprocal-, and Robertsonian translocation. Reciprocal translocation is a chromosome abnormality caused by exchange of parts between non-homologous chromosomes.
How many chromosomes do you have?
You have 46 chromosomes or 23 pairs in the nucleus of each body cell. 23 from mom and 23 from dad Gene = a segment of DNA that codes for a protein, which in turn codes for a trait (skin tone, eye color, etc); a gene is a stretch of DNA. There is a gene for every protein your body has to make.