Essential Idea: Every living organism inherits a blueprint for life from its parents

1. A heritable factor that consists of DNA and influences a specific characteristic is ...
  • A. a mitochondrion
  • B. a gene
  • C. a chromosome
  • D. a nucleotide
2. Where could genes be located in a bacterium?
  • A. Nucleoid only
  • B. Nucleoid + Plasmid
  • C. Ribosome + Plasmid
  • D. Nucleoid + Plasmid + Ribosome

Q3+4: In pea plants there is a gene controlling the height of the plant.

3. The specific position of this gene on a chromosome is called a ...
  • A. gene site
  • B. codon
  • C. locus
  • D. centromere
4. Pea plants may be tall or short. This is controlled by alternative forms of the gene called ...
  • A. chromosomes
  • B. alleles
  • C. loci
  • D. homologues

Q5-7: In normal haemoglobin the sixth codon of the gene, HbA, for haemoglobin is GAG. This codes for the amino acid glutamic acid.


5. When the protein of haemoglobin is made in the cell, what would be the bases in the anticodon for glutamic acid?

  • A. GAG
  • B. CUC
  • C. AGA
  • D. CTC
6. Sickle cell anaemia is the commonest genetic disease in the world. It is caused by a change in the allele for normal haemoglobin HbA to HbS. This causes the red blood cells to become sickle shaped.

blood cells with sickle cell anemia
Image of blood of a human with sickle cell anaemia

Ed Uthman
CC-BY-SA 2.0

6. What is thought to be the origin of the HbS allele?

  • A. A different species
  • B. A mutation of the HbA gene
  • C. An infection
  • D. It is unknown
7. The diagram shows part of the wheel of RNA codons coding for each amino acid.


section of RNA coding table


When the HbS allele is formed the second base of the codon is changed from A to U. Which amino acid is made as a result of this change?

  • A. Gly, Glycine,
  • B. Glu, Glutamic acid
  • C. Ala, Alanine
  • D. Val, Valine

8. Which of the following is correct?

I. In humans the genome consists of the DNA in the chromosomes.

II. In humans the genome consists of the DNA in the chromosomes and the DNA in the mitochondrion

III. In plants the genome consists of the DNA in the chromosomes, the mitochondrion and the chloroplasts

  • A. I only
  • B. I and II
  • C. II only
  • D. II and III
9. The Human genome project was begun in 1990. When was the entire base sequence of human genes completed?
  • A. 1993
  • B. 2000
  • C. 2003
  • D. It has not been completed
10. How many protein-encoding genes do scientists think are present in the human genome?
  • A.  20 - 25,000
  • B.  30 - 40,000
  • C.  65 - 75,000
  • D.  more than 100,000