Term | Definition |
What are Chromosomes? | Long molecules of DNA |
What is a Genome? | Entire genetic material of an organism |
What is a Gene? | A short length of a chromosome |
What do genes determine and what else? | Proteins and the type of protein |
The production of different proteins controls what? | Different characteristics like Dimples, and how organism functions |
Genes can exist in | Different versions, gives different form of characteristics e.g blue or brown eyes |
What are differences in species called? | Variation |
Genotype | all of the Genes and alleles |
Phenotype | Characteristics it displays |
Organisms genes are | Inherited |
Environmental variations | Leaves can be yellow, height |
Continuous Variation | No distinct categories |
Discontinuous Variation | Distinct Categories |
Mutations | Changes to the Genome, rare random changes, changes to the DNA bases |
Sexual Reproduction | Genetic information from 2 organisms (Father, Mother combined) to produce offspring which are genetically different |
Gametes | Contain half number of chromosomes, they are haploid |
How many chromosomes do Haploid contain? | 23 |
How many chromosomes do Diploid contain? | 46 |
How are Gametes produced? | Meiosis |
Meiosis is.. | Type of cell division, only in reproductive organs |
Explain Division 1 of Meiosis (1.) | Divides and DUPLICATES it's DNA, 1 each arm, X chromosome is exact copy |
Explain Division 1 of Meiosis (2.) | Chromosomes LINE UP in pairs at centre, one from dad and mom. |
Explain Division 1 of Meiosis (3.) | PAIRS PULLED APART, so new chromosome only has 1 each, SOME of dad and mom chromosomes go into new cell |
Explain Division 1 of Meiosis (4.) | Each new cell has MIXTURE of mom and dad chromosomes mixing up genes create genetic variation |
Explain Division 2 of Meiosis (5.) | Chromosomes line up again in centre , arms of chromosomes are PULLED APART |
Explain Division 2 of Meiosis (6.) | You get 4 HAPLOID GAMETES, each has single set of chromosomes, gametes are GENETICALLY DIFFERENT |
Sex Chromosomes control... | If your're male or female |
How many pairs of chromosomes are there in the body? | 23 pairs |
What is the 23rd pair labelled? | Labelled XY |
Males have what Chromosomes? | XY |
Females have what chromosomes? | XX |
Lack of Y chromosomes causes.... | female characteristics |
Y chromosome carries gene which... | Makes an embryo develop into a male |
Females always.... | Have 2 X chromosomes develop in a different way |
Asexual reproduction involves... | Mitosis |
Explain how asexual reproduction is different? | Only 1 parent, child genetically identical
Happens by Mitosis
New cell has same genetic information, it's a clone |
Alleles | Different versions of the same gene |
Characteristics caused by recessive alleles... | Appears when both alleles are recessive |
Homozygous | 2 same alleles for that gene (CC, cc) |
Heterozygous | 2 different alleles for that gene |
Classification | Organising living organisms into groups |
Natural classification systems | Use Evolutionary relationships |
Natural selection increases.. | Advantageous Phenotypes |
Artificial Classification systems.. | Use Observable Features |
Evolution | Change in inherited characteristics |
Bacteria | Can evolve and become Antibiotic-Resistant |
Fossils | Remains of the plants and animals |