topic 3: genetics

Question 1

how do bacteria reproduce

Answer 1

asexually through binary fission

Question 2

pros and cons of sexual reproduction

Answer 2

Pro - Because gametes fuse it leads to a large amount of variation

Pro - Population is less likely to wiped out by a disease or extreme event

Pro - Species can adapt to changing conditions by evolution

Con - It requires two parents

Con - Individuals may have have to spend large amounts of time and energy searching for a mate

Con - Many species spend resources impressing their mates even though it doesn’t aid survival

Question 3

what is a genotype

Answer 3

the collection of genes an organism has

Question 4

what is a gene

Answer 4

a section of DNA that controls part of a cells chemistry

Question 5

what is a phenotype

Answer 5

the physical characteristics of an organism

(something you can see!)

Question 6

what does meiosis create

Answer 6

4 genetically diverse haploid cells, which specialises into different sex cells

Question 7

why is sexual reproduction better from asexual

Answer 7

.Allows for genetic variation/diversity

.This can allow for genetic mutation that can help individuals in a species to adapt and survive over generations

.

Question 8

Which bases go together

Answer 8

.A+T
.C+G

Question 9

what are the names of the four bases in order A,T,C,G

Answer 9

Adenine
Thymine
Cytosine
Guanine

Question 10

what is DNA short for

Answer 10

DNA (deoxyribonucleic acid)

Question 11

what is a Genome

Answer 11

the entire genetic makeup

Question 12

what is the name for the shape of DNA

Answer 12

double helix

Question 13

what are the pair of bases held together by

Answer 13

weak hydrogen bonds

Question 14

how many pairs of bases create an amino acid

Answer 14

three

Question 15

why is the structure of DNA described as

Question 16

Cytosine and Thymine are bigger than Adenine and Guanine

True?

Answer 16

No

Question 17

what is a chromosome

Answer 17

contains DNA

Question 18

why are proteins polymers

Answer 18

they are made up of many amino acids joined together

Question 19

differences between DNA compared mRNA and tRNA

Answer 19

different bases than DNA
DNA is in a double helix formation whereas mRNA and tRNA are both single stranded

Question 20

why is washing liquid used to extract DNA

Answer 20

.breaks down the cell membrane and the nucleic membrane

Question 21

what is each triplet of three bases

Answer 21

codon

Question 22

what is an allele

Answer 22

a version of a gene

Question 23

what is a mutation

Answer 23

a change in the base of a DNA molecule

Question 24

what could cause a mutation

Answer 24

radiation

Question 25

what is a gene

Answer 25

A piece of DNA that codes for a single protein

Question 26

what is DNA

general idea

Answer 26

blueprint/code to make an individual

Question 27

what is a chromosome

Answer 27

a long thread like strand of DNA found in the nucleus of a cell

Question 28

what is a domminat allele

Answer 28

an allele which overrides other alleles (written with a capital letter)

Question 29

what is the difference between homo and heterozygous

Answer 29

Homozygous is when your alleles are the same

Heterozygousl is two different the alleles

Question 30

what was the work of Mendel

Answer 30

He cross breed peas to detect the power of inheritance

Question 31

What is true breeding

Answer 31

when two pure organisms are bred with each other to determine which is the receive and which is the dominant

Question 32

what is a codon

Answer 32

each amino acid is coded for by a sequence of three bases called condons

Question 33

what are mutagens

Answer 33

something that causes/increases chance of a mutation

Question 34

how can changes in the DNA sequence affect individuals and how could DNA sequencing a person influence treatments

Answer 34

.DNA has 4 different bases, and changes to the DNA are mutations, this will result in different alleles for these genes and so can affect the phenotype/produce variation

.DNA sequencing of an individual can identify genetic diseases, identify the risks of developing different disease and impact the individual to modify their lifestyle or seek medical treatment.

Question 35

how can non-coding DNA still effect likelihood of mutations

three bullets

Answer 35

mutations in this region of DNA can effect how easy it is for RNA Polymerase to bind to it for protein synthesis

this effects how much mRNA is transcribed and so how much protein is made.

depending on the function of the protein how much is made may effect an organisms phenotype

Question 36

how can genetic variants in coding DNA lead to changes in phenotype

Answer 36

.mutations occur in the base sequence within the gene of an organism
.this genetic variant could code for a different sequence of amino acids and so change the shape of the final protein produced changing its activity
.(activity of an enzyme could increase, decrease or stay the same)
.this can change the characteristics due to activity.

Question 37

how can genome mapping help in medicine

Answer 37

.determine the risk of developing certain diseases caused by alleles of genes
.provide information on which course of treatment is best for individuals as certain alleles can affect how medicine works on people.

Question 38

when do most mutations occur and explain the process

Answer 38

.during cell division, mutations can happen when there is a mistake in copying DNA during cell division. Where one base in a DNA sequence is replaced by another.
(it can happen naturally or due to radiation or certain substances)

Question 39

why do most genetic mutations not effect the phenotype

Answer 39

the change occurs in the DNA sequence of a non-coding region of the DNA