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2019 Science Exam
Semester 2 (2019) Exam Revision
Question | Answer |
---|---|
chromosomes | thread-like structures in the nucleus; |
Number of chromosomes in a body cell | 46 |
Number of Chromosomes in a gamete | 23 chromosomes in sperm or egg |
Know the structure of DNA | alternating sugar and phosphate units |
mitosis | Mitosis-daughter cell identical to parent cell |
meiosis | meiosis-daughter cell has half of number in parent cell |
gamete formation | Gametes formation can be observed in gonads |
when the sex of an individual is determined | when the egg is fertilised by the sperm |
where chromosomes are found | in the nucleus of most cells of your body |
phenotype | the observable expression of these genes from a genotype |
genotype | The genetic make up |
Know what an allele is | alternative forms of a gene found at the same locus on a chromosome. |
homozygous | having two alleles the same on homologous chromosomes |
heterozygous | having two different alleles on homologous chromosomes |
Chromosomes in Female Animals | In most animals, the female has two X chromosomes |
Chromosomes in Male Animals | 1 X and 1 Y Chromosome |
X and Y Chromosomes use in a human | Sex Determination |
Know what DNA | deoxyribonucleic acid |
what ‘bases’ you find within DNA | adenine, cytosine, thymine and guanine |
rDNA technology | Technology whereby the DNA of one organism is recombined with genes from another organism. |
stem cells | Cells in an embryo are initially identical. |
the process of differentiation | As the embryo matures, cells take on specific characteristics and become different from each other |