Inheritance Flashcards
What is the diploid number?
The number of chromosomes in a body cell.
What is the haploid number?
The number of chromosomes in a gamete.
What is a nucleotide?
The monomer for DNA. It is a compound made from a phosphate group, a sugar, and a base.
What is a gene?
A length of DNA that holds the code for one characteristic.
What type of sugar is in DNA monomers?
A pentose sugar.
What are the 4 bases, and how do they pair together?
- T and A
- G and C
How many bases code for one amino acid.
3
A triplet.
What did Mendel discover?
- That characteristics where passed down from parents to offspring
- Some of the characteristics could be recessive
What is a genotype?
The full set of genes that an organism has.
What is a phenotype?
The observable characteristics of an organism.
What is an allele?
Different versions of the same gene.
What does homozygous mean?
Organisms that have homologous chromosomes which have the same allele.
What does heterazygous mean?
Organisms that have homologous chromosomes which have different alleles.
What is a dominant allele?
Only one copy is needed for the allele to be expressed.
What is a recessive allele?
An allele that is only expressed if there is no dominant allele.
What is cystic fibrosis?
- Genetic disorder
- Affects cell membranes
- Causes unusually thick mucus to be produced
How are people affected by cystic fibrosis?
- Low energy levels (slow diffusion of oxygen into blood - reduces respiration)
- Difficulty gaining weight (blocked pancreas duct - enzymes don’t reach the small intestine)
Is cystic fibrosis caused by a recessive or dominant allele?
A recessive allele.
What is polydactyly?
- Genetic disorder
- Causes more than 5 fingers/toes to grow
Is polydactyly caused by a recessive or dominant allele?
A dominant allele.
What is the order of classification?
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Where does the binomial Latin name for species come from?
Genus then species
What was Lamarck’s theory?
Inheritance of acquired characteristics.
When do two groups of organisms become distinct species?
when they can no linger reproduce to produce fertile offspring.
What are the 3 ways that fossils are formed?
1. Bones are fossilised (they mineralise and turn to rock within sedimentary rocks)
2. Impressions
3. Preservation (in conditions where the organism can not decompose)
How are genes cut form DNA and put into plasmids?
Using enzymes.
What is tissue culture?
Cloning plants by taking cells and growing them in agar jelly.
What are the two method of animal cloneing?
- Embryo transplants
- Adult cell cloning
How does embryo transplants work?
- Embryo produced using sperm and egg
- Cells from embryo are separated
- Multiple identical embryos are produced
- These are implanted into surrogate mothers
How does adult cell cloning work?
- Donor nucleus is fused using a electric shock with an empty egg cell (nucleus removed)
- This then forms an embryo
- Embryo is implanted into surrogate mother
What is the difference between embryo transplants and adult cell cloning?
- Embryo transplants create identical offspring that are different from the parents
- Adult cell cloning creates a clone of the parent
