sb3 Flashcards
What are the advantages and disadvantages of asexual reproduction?
Advantages -
—> don’t need to find a mate
—> rapid reproductive cycle
Disadvantages -
—> no variation
What are the advantages and disadvantages of sexual reproduction?
Advantage -
—> variation in population
Disadvantage -
—> need to find a mate
What is the result of meiosis?
- 4 daughter cells ( divides twice )
- all haploid
- all genetically different
What is DNA?
- two strands forming a double helix
- strands linked by complimentary base pairs linked with weak hydrogen bonds
- nucleotides that have a sugar and phosphate group with one of the four bases
What is the genome?
Entire DNA of an organism
What is a gene?
A section of DNA that codes for a specific protein
What do we see after DNA is extracted from fruits?
A white precipitate at the top of the tube ——> this is the DNA
Why do we add pineapple juice when extracting DNA?
Contains enzyme called bromelain which breaks down proteins attached to the DNA
—> helps us see DNA more clearly
Why do we add ethanol when extracting DNA?
Causes DNA to precipitate out of the solution
What is a gamete?
An organisms reproductive cell
E.g sperm and egg
What is an allele?
A different version of the same gene
What is a dominant allele?
Only one of the alleles is needed for it to be expressed (always expressed)
What is a recessive allele?
Both alleles need to be recessive in order for it to be expressed
What is a genotype?
The alleles an organism has e.g Aa
Whats a phenotype?
The physical characteristics of an organism