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YEAR 10 REVISION. GENETICS. 1. Write true or false for each response:. All body cells divide by a process of cell division called meiosis. FALSE Sex cells have 23 pairs of chromosomes FALSE Your check cells have 46 chromosomes in the nucleus TRUE.
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YEAR 10 REVISION GENETICS
1. Write true or false for each response: • All body cells divide by a process of cell division called meiosis. FALSE • Sex cells have 23 pairs of chromosomes FALSE • Your check cells have 46 chromosomes in the nucleus TRUE
How do male and female chromosomes differ? • MALE = XY • FEMALE =XX
In pea plants, purple(P) is dominant over white(p) flowers. Which genes would be present in these cases? • Pure-bred white pp • Hybrid purple Pp • Pure-bred purple PP
Use a punnet square to predict the effect of a cross between a hybrid short-haired dog(Ss) and a long haired dog(ss). Short hair in dogs is dominant and long hair is recessive. Show all the genotypes and phenotypes possible.
GENOTYPE: 50%Ss: 50%ss • PHENOTYPE: 50%short:50%lonh
True or false • Proteins carry the genetic code FALSE • DNA is a large molecule shaped like a double helix TRUE • The genetic code is a sequence of organic bases in sets of three. TRUE
Write the complementary base sequence for this part of a DNA molecule. ACGATGAATTGC TGCTACTTAACG
If 2 forms of a gene are resperesented by A and a , then the genotype AA could be described as: • A. heterozygous • B. homozygous recessive • C. Hybrid • D. Homozygous dominant
Chromosomes are normally found: • A. in the genes of an organisms • B. In the nucleus of a cell • C. Only in skin cells • D. Only in the sex cells of an organism
The alternative forms of genes are called • A. mutants • B. alleles • C. aliens • D. copies
The chance that: • A. A sperm will contain a Y chromosome is 100% • B. An egg will contain a Y chromosome is 50% • C. A sperm will contain an X chromosome is 0% • D. An egg will contain an X chromsome is 100%
TRUEOR FALSE? • All human cells contain an X and Y chromosome FALSE • The sex of a child is determined by the father’s sex cells TRUE • Chromosomes are made of deoxyribonucleic acid TRUE • In order for a person to be left handed (recessive) both parents must be left handed FALSE • Identical twins have different genotypes FALSE