Year 10 Biology Practice Exam PDF

# Year 10 BIOLOGY practice exam ## **Multiple Choice Questions** 1. In humans, brown eyes seem dominant over blue eyes. A brown-eyed man marries a blue-eyed woman and they have 8 children, all brown-eyed. The probable genetic makeup of the father, mother, and children, respectively, is: (1 Point)...

# Year 10 BIOLOGY practice exam ## **Multiple Choice Questions** 1. In humans, brown eyes seem dominant over blue eyes. A brown-eyed man marries a blue-eyed woman and they have 8 children, all brown-eyed. The probable genetic makeup of the father, mother, and children, respectively, is: (1 Point) - (a) BB, bb, Bb - (b) BB, bb, BB - (c) Bb, bb, BB - (d) Bb, bb, bb 2. If brown eyes are represented with a B and blue eyes represented as a b, what color eyes would someone have if their genotype is Bb? (1 Point) - (a) Blue - (b) Brown - (c) Hazel - (d) Green 3. If brown eyes are represented with a B and blue eyes represented as a b, what color eyes would someone have if their genotype is bb? (1 Point) - (a) Blue - (b) Brown - (c) Hazel - (d) Green 4. Nucleotides are made up of (1 Point) - (a) Bases, Amino Acid, Deoxyribose - (b) Bases, Phosphate, sugar - (c) Bases, Protein, Sugar - (d) Bases, Hormones, Protein 5. According to the base pairing rule, G (guanine) pairs with what other base? (1 Point) - (a) A (adenine) - (b) T (thymine) - (c) C (cytosine) - (d) M (myosine) 6. According to the base pairing rule, A (adenine) pairs with what other base? (1 Point) - (a) G (guanine) - (b) T (thymine) - (c) C (cytosine) - (d) M (myosine) 7. If two alleles are the same (BB) it is said to be (1 Point) - (a) Homozygous Dominant - (b) Homozygous Recessive - (c) Heterozygous Recessive - (d) Heterozygous Dominant 8. If two alleles are the same (bb) it is said to be (1 Point) - (a) Homozygous Dominant - (b) Homozygous Recessive - (c) Heterozygous Recessive - (d) Heterozygous Dominant 9. According to the base pairing rule what letters match together? (1 Point) - (a) A and G - (b) C and G - (c) C and A - (d) G and T 11. DNA looks like: (1 Point) - (a) A straight line of threads - (b) A double helix - (c) linear - (d) An X shape 12. How many chromosomes are in our sex cells: (1 Point) - (a) 21 - (b) 22 - (c) 23 - (d) 24 13. The sex chromosomes for females is: (1 Point) - (a) ZZ - (b) ZY - (c) XY - (d) XX 16. Transcription is: (1 Point) - (a) Going into the army. - (b) The process of sorting chromosomes - (c) The process of making sugars. - (d) The process of copying the DNA message. 17. Translation is: (1 Point) - (a) Speaking in another language - (b) The process of sorting chromosomes - (c) The process of making sugars. - (d) Reading the genetic codes to make amino acids 18. If dimples cheeks (D) are dominant to non dimpled cheeks (d), what proportion of offspring with dimpled cheeks may one expect if 2 non dimpled individuals mate? (1 Point) - (a) 0% - (b) 75% - (c) 50% - (d) 100% 20. Human skin cells each contain: - (a) 23 chromosomes - (b) 46 chromosomes - (c) 46 pairs of chromosomes - (d) A single sex chromosome 22. In chimpanzees, straight fingers are dominant to bent fingers. What percentage of straight fingered chimpanzees would you expect if a heterozygous straight (Ss) and a homozygous bent (ss) mate? (1 Point) - (a) 100% - (b) 75% - (c) 25% - (d) 50% 23. The phenotype of an allele shows: (1 Point) - (a) Its genetic characteristics - (b) Its physical characteristics - (c) Its number of chromosomes - (d) Its cell count. ## **Short Answer Questions** 1. The section of DNA below shows the sequence of bases on one side of the DNA molecule. Write the letter of the complementary bases on the empty line on the right-hand strand. (6 Points). | | | | |---|---|---| | G | S | C | | A | P | T | | G | S | C | | T | P | A | | A | S | T | | C | P | G | | A | S | G | 2. Diagrams A shows a type of cell division. a. Write the names of the type of cell division on the line beneath the diagram (1 mark) Meiosis b. Describe the cells produced in this type of cell division (type, number of chromosomes, purpose etc) (4 marks) - They are called gametes (sex cells) - They have 23 chromosomes, half that of all other cells. - They have half the number, so that when one from mum and dad combine (fertilise) the embryo will have 23 pairs of chromosomes. 3. In guinea pigs, black coat colour is dominant to brown coat colour. (12 Points) (a) Select an appropriate symbol to represent the alleles for black and brown coat colour. - B = Black, b = Brown (b) What colour offspring would you expect from the following crosses? (i) Homozygous black x homozygous brown: | | b | b | |---|---|---| | B | Bb | Bb | | B | Bb | Bb | - 100% Black (ii) Heterozygous black x heterozygous black: | | B | b | |---|---|---| | B | BB | Bb | | b | Bb | bb | - 75% Black, 25% Brown (iii) Heterozygous black x homozygous brown: | | b | b | |---|---|---| | B | Bb | Bb | | b | bb | bb | - 50% Black, 50% Brown