B1-you and your genes

Question 1

what’s a genome?

Answer 1

the genetic make up of an organism.

Question 2

where is genetic material found in humans and animals?

Answer 2

the nucleus.

Question 3

what are eukaryotic organisms? (give examples)

Answer 3

cells that have a nucleus.
e.g. plants, fungi, protists

Question 4

what’s a prokaryotic organism?

Answer 4

an organism that does have a nucleus.
e.g. bacteria

Question 5

what are chromosomes?

Answer 5

long threads of genetic material made up of DNA.

Question 6

describe DNA.

Answer 6

-consists of 3 strand twists which form a double helix.
-made from small molecules called nucleotides.
-it’s a natural polymer.

Question 7

what’s a gene?

Answer 7

a region of DNA, they contain instructions that cells use to make protein.

Question 8

describe proteins.

Answer 8

structural- collagen,found in skin.
functional- amylase, speeds up chemical reactions.
-made from amino acids.
-fight bacteria and viruses.
-carry oxygen.
-build cells and tissues.
-move muscles.

Question 9

what are alleles?

Answer 9

2 copies of a gene.

Question 10

what’s a genetic variant?

Answer 10

a different version of a gene.
they are caused by small changes in the DNA.
Can be harmful.

Question 11

what’s a genotype?

Answer 11

the combination of alleles for a gene.

Question 12

what’s a phenotype?

Answer 12

the features that result from the information in the DNA + interactions with the environment.
genome + environment = phenotype

Question 13

what’s a nucleotide made up of?

Answer 13

-a common sugar (deoxyribose).
-a phosphate group.
-a base.

Question 14

what are the 4 bases used in DNA?

Answer 14

(A) adenine
(T) thymine
(G) guanine
(C) cytosine

Question 15

how do you pass on genetic information?

Answer 15

through base pairing, this means it’s possible to make exact copies of DNA.

Question 16

what’s a genetic code?

Answer 16

the protein made using the information in the genome are vital to the development and functioning of organisms.

Question 17

what’s a triplet code?

Answer 17

3 bases on a DNA strand code for 1 amino acid.
GGC = glycine
CGG = arginine
TAT = tyrosine

Question 18

what happens in the ribosomes?

Answer 18

amino acids are joined together to make proteins in the cytoplasm.

Question 19

how do ribosomes get the instructions for making protein?

Answer 19

-the triplet code is read and used to build the messenger RNA.
-that then carries genetic code to the ribosomes.
-the code in the mRNA controls the order that amino acids are joined together to make protein.

Question 20

what’s the difference between DNA and mRNA?

Answer 20

mRNA has:
-only 1 strand.
-a base called uracil (U) instead of thymine (T).

Question 21

what’s point mutation?

Answer 21

it substitutes 1 nucleotide base, may not affect the structure of the protein and its function.

Question 22

what’s insertion mutation?

Answer 22

an addition of 1 or more nucleotides into a segment of DNA.

Question 23

what’s deletion mutation?

Answer 23

it changes every triplet until the STOP, it may change many amino acids and affect the shape of the protein and its function.

Question 24

what are gametes?

Answer 24

they pass on genetic information.
they are made from body cells.

Question 25

how can you tell that an embryo is male?

Answer 25

-it produces testes, this is caused by the SRY gene, they produce androgens.
-androgens make the embryo develop male characteristics.

Question 26

what are hormones?

Answer 26

they are a group of proteins that control many processes in cells.
they travail via the bloodstream.

Question 27

explain gene testing.

Answer 27

comparing genomes of individuals with and without disease can help to identify alleles associated with disease.
this can help doctors prescribe the correct drugs.

Question 28

explain gene technology.

Answer 28

when the genome is modified to change an organism’s characteristics.

Question 29

benefits of gene technology.

Answer 29

could help us provide for the needs of society by improving healthcare and producing food for the growing population.

Question 30

downside of gene technology.

Answer 30

-false positives/negatives.
-miscarriages.
-no long term studies for adverse reactions.