Biology-Genetics Flashcards
What is sexual reproduction
Involves the fusion of male and female gametes, resulting in offspring with genetic variation
What is asexual reproduction
Involves a single parent and produce genetically identical offspring through mitosis
What are the advantages of sexual reproduction
Creates genetic diversity which can enhance survival in changing environments
What are the advantages of asexual reproduction
Faster reproduction and doesn’t require a partner
What is meiosis
A process that produces 4 non identical haploid gametes
What are the 2 divisions of mitosis
One reduces the chromosomes by half and the second separates the chromatids
Why does genetic variation arise
Due to the random assortment of chromosomes and crossing over during mitosis
What shape is a DNA strand
Double helix
What are DNA composed of
Nucleotides which contain sugar,phosphate and a base
What is a genome
A genome is the complete set of genetic material in an organism
What is a gene
A gene is a short section of the DNA and each gene codes for many amino acids
Give the process of extracting DNA from fruit
Gently mix together 50ml cold water, half a teaspoon of salt and 10ml washing up liquid. Heat this mixture at 50°C for 5–10 minutes.
Peel the skins of a kiwi and chop into small pieces.
Add the solution from Step 1 to the kiwi.
Filter the solution and pour the filtrate into a test tube.
Add 10ml of pineapple juice to the filtrate
Add 2 teaspoons of cold ethanol to the solution and wait 10 minutes.
Describe protein synthesis
The code is copied by mRNA which is transcription. Which is then taken to the ribosome which assembles amino acids into polypeptides then proteins which is called translation. These are then folded into shape
What are mutations
Mutations are changes in the DNA sequence
How do mutations affect us
They can affect the structure and function of proteins leading to genetic disorders
How are traits determined
By alleles which can be dominant or recessive
What are dominant alleles
Shows its effect if only one copy is present and represented by a capital letter
What are recessive alleles
Only shows if both copies are recessive and is represented by a lowercase letter
What is homozoygus
Two identical alleles
What are hetrozygus
Two different alleles
How did the human genome project help us
Improved our understanding of genes linked to diseases, Helped in making personalised medicines.
