Genes Lecture 1

Question 1

rise of complex life

Answer 1

merging of energy producing alpha photobacterium and information containing Archaea

Question 2

what was the original cell

Answer 2

Loki
discovered in hydrothermal vents in Norway
Asgard-Cell Archaea

Question 3

telomeres

Answer 3

chromatin structure that prevents DNA damage/ degradation during replication

Question 4

features of telomeres

Answer 4

contain loop structures to stop recombining DNA and forming/ fusing with other chromosomes

Question 5

which cells contain telomerase and why

Answer 5

embryonic stem cells, cancer cells and germ cells to prevent chromosomes from getting shorter

Question 6

how many genomes do eukaryotes have

Answer 6

2: nuclear and mitochondrial

Question 7

features of mitochondrial genomes

Answer 7

DNA not bound to histones
small and circular histones
maternal inheritance
similar to a bacterial cell which supports the endosymbiotic model of eukaryotic evolution

Question 8

intergenic sequences

Answer 8

DNA sequences between genes

Question 9

intragenic sequences

Answer 9

DNA sequences within genes e.g. introns

Question 10

what type of inheritance does mitosis give rise to

Answer 10

somatic

Question 11

mitosis

Answer 11

both daughter fells inherit one copy of the duplicated genome

Question 12

special case of mitosis

Answer 12

some cytoplasmic material can be asymmetrically distributed leading to reprogramming of daughter cells

Question 13

what inheritance does meiosis give rise to

Answer 13

germ line

Question 14

meiosis

Answer 14

haploid genome: one copy of the genome and enables sexual reproduction

Question 15

symmetrical division of mitosis

Answer 15

daughter cell

Question 16

asymmetrical division of mitosis

Answer 16

produces differentiated daughter cells and stem daughter cells

Question 17

why is mitosis asymmetrical division beneficial

Answer 17

prevents premature exhaustion of adult stem cells such as muscle gut and blood cells

Question 18

karyotypes

Answer 18

allows observation of a full set of human chromosomes

Question 19

difference between male and female meiosis

Answer 19

have different timings
males produce haploids directly whereas females have an extra step: in meiosis 1: formation of a polar body and in meiosis 2: ejection of a polar body