Unit 2: KS 2- Genomes, Genes & Alleles

Question 1

What does genome mean?

Answer 1

The complete set of genetic material present within a haploid set of chromosomes

Question 2

What is a gene?

Answer 2

Specific segment of DNA on a chromosome, which code for different traits.

Question 3

What is an allele?

Answer 3

A different version of the same gene

Question 4

What are the 4 Nucleotide bases?

Answer 4

Adenine, Thymine, Guanine and Cytosine

Question 5

How do the bases pair?

Answer 5

A pairs with T

C pairs with G

Question 6

Which scientist developed the concept of genes?

Answer 6

Gregor Mendel

Question 7

What is meant by the term dominant?

Answer 7

A trait which is expressed in a heterozygous pair

Question 8

What is meant by the term recessive?

Answer 8

A trait which is NOT expressed in a heterozygous pair

Question 9

What is a Karyotype?

Answer 9

Visual representation of chromosomes, sorted into homologous pairs from largest to smallest.

Question 10

What genetic difference does a person with Down Syndrome have?

Answer 10

3 chromosomes in the 21st group instead of 2

Question 11

What genetic difference does a person with Kinefelter Syndrome have?

Answer 11

3 sex chromosomes instead of 2

Question 12

What are the 3 types of Chromosomal changes?

Answer 12

Duplication, Deletion and Translocation

Question 13

What does phenotype mean?

Answer 13

Visual expression of an organisms genetic makeup

Question 14

What does genotype mean?

Answer 14

Genetic makeup which determines the phenotype

Question 15

What does autosome mean?

Answer 15

Any chromosome which isn’t a sex chromosome

Question 16

What does homozygous mean?

Answer 16

Having 2 identical alleles

Question 17

What does heterozygous mean?

Answer 17

Having 2 different alleles

Question 18

What does locus mean?

Answer 18

Location of a gene on a chromosome

Question 19

What is a polygene?

Answer 19

Group of genes which express a phenotype only when all shown

Question 20

What is an example of a Polygenic Trait?

Answer 20

Height, Eye Colour, Skin Colour etc

Question 21

What does autosome mean?

Answer 21

22 pairs of chromosomes (not sex chromosomes)

Question 22

What does non-homologous pair mean?

Answer 22

Refers to a non-matching pair

Question 23

What is the Kinetochore?

Answer 23

Attachment point for spindle fibre (surrounds centromere)

Question 24

What is the Telomere?

Answer 24

Ends of chromosome, prevent chromosomes from sticking together

Question 25

What is co-dominance?

Answer 25

Heterozygous organism showing both alleles in phenotype

Question 26

What is dominant?

Answer 26

Refers to trait which IS expressed in heterozygous pair.

Question 27

What is recessive?

Answer 27

Refers to trait which IS NOT expressed in a heterozygous pair

Question 28

Name 2 benefits of The Human Genome Project:

Answer 28

Helps to understand Human Evolution | Can be used to develop treatments or diagnoses for genetic disorders

Question 29

What genetic difference does a person with Turner's Syndrome have?

Answer 29

1 sex chromosome instead of 2 (XO)

Question 30

What is DNA?

Answer 30

Chain of nucleotides which contain the genetic instructions used to encode life

Question 31

What is Chargaff's Rule?

Answer 31

Corresponding bases have equal proportions | eg. A and T

Question 32

What is the difference between Ideogram and Karyotype?

Answer 32

Ideogram shows individual chromosomes, karyotypes shows homologous pairs

Question 33

What is the difference between an Autosome and a Sex Chromosome?

Answer 33

Autosomes control body characteristics and somatic cells, sex chromosomes determine the sex of individual

Question 34

What is the difference between Haploid and Diploid?

Answer 34

Haploid is number of chromosomes in gamete, diploid is number of chromosomes in somatic cell

Question 35

What is the difference between Centromere and Kinetochore?

Answer 35

Centromere is where sister chromatids join, Kinetochore is protein structure which forms spindle fibres

Question 36

What is the difference between Monosomy and Trisomy?

Answer 36

Monosomy is when 1 chromosome is present, Trisomy is when 3 chromosomes are present

Question 37

What is a homologous chromosome pair made of?

Answer 37

1 Paternal chromosome and 1 Maternal chromosome

Question 38

What is Epigenetics?

Answer 38

The alteration of the physical structure of DNA, which affect how genes are read

Question 39

What is continuous variation?

Answer 39

Variation which has no limit on the number of possibilities which can occur. Eg Height

Question 40

What is discontinuous variation?

Answer 40

When individuals can be grouped into categories based on limited outcomes. Eg Blood Type