Biology End-Topic Test - Year 10 Flashcards
What is Nucleus
Membrane-enclosed organelle inside cell that contains chromosomes
- They contain an array of holes/pores
What is Ribosome
Is the site of protein synthesis in the cell
Ribosome reads messenger RNA sequence and translates into genetic code
What is Centriole
Help determine location of nucleus and other organelles
Plays role in cell division, involved in formation of mitotic spindle
- Essential for separation of chromosomes during mitosis
What was Gregor Mendel’s Results, and How Did He Find Them
Mid-1800s, Mendel accurately concluded that genes exist in pairs (One from each parent), and that they can separate and form pairs again in next generation
- Did this by experimenting on peas
What 2 Principles Did Gregor Mendel Find
Principle of Segregation
Principle of Independent Assortment
What is Principle of Segregation
Traits/Characteristics of living things exist in pairs of genes
Genes must become separated/segregated before passed onto offspring
Every organism inherits one set of genes from mother, one set of genes from father
What is Principle of Independent Assortment
Inheritance of one set of gene from one parent, is independent from inheritance of one set of gene from other parent
- Eg. If you inherit blue eyes from mother, doesn’t mean you also inherit blonde hair and small nose from mother
- They are inherited independently from eachother
How to Determine if Offspring is Male or Female
Every individual has an X chromosome, since both the chromosomes from both eggs of mother has single X chromosome (Meiosis)
For the two sperm cells, one have single X chromosome, one have single Y chromosome
To determine if boy or girl, it is a race between X-sperm and Y-sperm, to see which one fertilises the egg cell first
- If X-sperm fertilises first, it is a girl
- If Y-sperm fertilises first, it is a boy
What is Allele
Different genes for the same characteristic
What is Phenotype
The characteristic or trait itself
What is Genotype
Unique combination of alleles for a gene inherited from parents
- Which combination you get is your phenotype
What is Homozygous
Where individuals have two of the same alleles - Homozygous
- Eg. BB, bb
What is Heterozygous
Where individuals have two different alleles for same gene - Heterozygous
- Eg. Bb
What is Hemizygous
Where individual has only one allele - Hemizygous
- Eg. B, b
What is a Punnet Square
2x2 square which shows genotypes