Unit 5 Herditary

Question 1

Describe the function of Meiosis 1 and 2

Answer 1

Function 1: Separates homologous chromosomes and produces two daughter cells

Function 2: separates sister chromosomes

Question 2

Describe Interphase 1

Answer 2

Interphase 1: centromeres are duplicated, DNA is copied, DNA is loose. Goes through G1 S G2

Question 3

Describe Prophase 1

Answer 3

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

Question 4

Describe Metaphase 1

Answer 4

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

Question 5

Describe Anaphase 1

Answer 5

Anaphase 1: The 2 homologous chromosomes of each pair separate and get pulled to opposite poles

Question 6

Describe Telophase 1and Cytokinesis

Answer 6

Telophase 1 and cytokinesis: DNA uncoils and nuclear envelopes reappear. Two new nuclei form. 2 haploid cells are produced

Question 7

Describe Interphase 2

Answer 7

Interphase 1: centromeres are duplicated, DNA is copied, DNA is loose. goes through g1 s g2

Question 8

Describe Prophase 2

Answer 8

chromosomes condense, the nuclear envelop starts to disappear but the nucleus remains intact, and the mitotic spindle forms and start attaching to chromosomes

Question 9

Describe Metaphase 2

Answer 9

The nucleus dissolves and the cell’s chromosomes condense and move together, aligning in the center of the dividing cell.

Question 10

Describe Anaphase 2

Answer 10

Chromosomes are separated into single chromosomes and are pulled to opposite sides of the cell.

Question 11

Describe Telophase 2 and Cytokinesis

Answer 11

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

Question 12

What are Mendel’s 3 laws?

Answer 12

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)

Question 13

What is Nondisjunction?

Answer 13

chromosomes don’t separate causes Mutations and can lead to downsyndrom

Question 14

What is Translocation?

Answer 14

sections of chromosomes move to different types of chromosomes ex chromosome 22 moves to chromosome 18 happens in prophase when chromosomes cross over

Question 15

what’s the purpose of protein synthesis

Answer 15

to create proteins

Question 16

Describe the purpose and location
what happens in transcription

Answer 16

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

Question 17

Describe the purpose and location
what happens in translation

Answer 17

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

Question 18

what’s an RNA polymerase?

Answer 18

a multi-unit enzyme that produces RNA molecules form a template of DNA through a process known as transcription[