Unit 5 Herditary Flashcards
Describe the function of Meiosis 1 and 2
Function 1: Separates homologous chromosomes and produces two daughter cells
Function 2: separates sister chromosomes
Describe Interphase 1
Interphase 1: centromeres are duplicated, DNA is copied, DNA is loose. Goes through G1 S G2
Describe Prophase 1
Prophase 1: (single) homologous chromosomes pair up and “cross over” forming a tetrad. Allows an exchange of DNA between homologous chromosomes
chromosomes condense, the nuclear envelop starts to disappear but the nucleus remains intact, and the mitotic spindle forms and start attaching to chromosomes
Describe Metaphase 1
Metaphase 1: The homologous pairs of chromosomes align in the middle of the dividing cell and the spindle fibres attach to them?
The nucleus dissolves and the cell’s chromosomes condense
Describe Anaphase 1
Anaphase 1: The 2 homologous chromosomes of each pair separate and get pulled to opposite poles
Describe Telophase 1and Cytokinesis
Telophase 1 and cytokinesis: DNA uncoils and nuclear envelopes reappear. Two new nuclei form. 2 haploid cells are produced
Describe Interphase 2
Interphase 1: centromeres are duplicated, DNA is copied, DNA is loose. goes through g1 s g2
Describe Prophase 2
chromosomes condense, the nuclear envelop starts to disappear but the nucleus remains intact, and the mitotic spindle forms and start attaching to chromosomes
Describe Metaphase 2
The nucleus dissolves and the cell’s chromosomes condense and move together, aligning in the center of the dividing cell.
Describe Anaphase 2
Chromosomes are separated into single chromosomes and are pulled to opposite sides of the cell.
Describe Telophase 2 and Cytokinesis
DNA uncoils and nuclear envelopes reappear. Two new nuclei form. 4 daughter cells are produced with a haploid set of unduplicated chromosomes (one set of chromosomes)
cytokinesis allows cell to divide and ensures equal distribution of cytoplasm to each daughter cell
What are Mendel’s 3 laws?
law of dominance dominate: BB Recessive bb
law of segregation: alleles are separated so that each individual gets only one copy of each chromosome
law of independence assortment: each trait/allele is inherited without influence from other traits/alleles (each segment gets 1 of each trait)
What is Nondisjunction?
chromosomes don’t separate causes Mutations and can lead to downsyndrom
What is Translocation?
sections of chromosomes move to different types of chromosomes ex chromosome 22 moves to chromosome 18 happens in prophase when chromosomes cross over
what’s the purpose of protein synthesis
to create proteins
Describe the purpose and location
what happens in transcription
purpose: creates several forms of RNA such as mRNA
location: nucleus
step one initiation: RNA polymers protein binds to the promoter region in the DNA complex this signals the DNA to unwind so that the helices enzyme can “read” the bases
step 2 elongation: the RNA strand get longer. RNA polymerase walks the one strand of DNA in the 5’ to 3’ direction and builds an mRNA strand
step 3 termination: end of transcription occurs when RNA polymerase crosses a stop sequence the mRNA strand is complete and detaches from the DNA. the DNA then rewinds back into a double helix
Describe the purpose and location
what happens in translation
purpose: to produce proteins from an RNA template
location: cytoplasm
step one initiation: the ribosomes made by RNAs bind to the start of the mRNA sequence then tRNA carrying an amino acid binds to a start Condon
step 2 elongation: the amino acid chain gets longer by amino acids being brought to the ribosomes by tRNAs and linked together to form a chain
step 3 termination: end of protein synthesis when the ribosome encounters a stop Condon ribosomes dissemble tRNAs and release the built polypeptide chain
what’s an RNA polymerase?
a multi-unit enzyme that produces RNA molecules form a template of DNA through a process known as transcription[
