Year 10 Biology Flashcards
(38 cards)
Where is DNA found?
The nucleus of a cell
What is a gene?
A segment of DNA
What shape does DNA have?
Double Helix
What is the building blocks of DNA?
Nucleotides
What are nucleotides made of?
Phosphate group, pentose sugar and nitrogenous base
What are the bases of DNA
Adenine, thymine, cytosine and guanine
Which base bonds with each other?
Adenine and Thymine bond
Cytosine and Guanine bond
What is the significance of protein?
It gives us our traits
How is DNA organised?
Into units called genes
How many pairs of chromosomes does a human have?
23 pairs
46 in total
What does diploid mean?
A pair of chromosomes in somatic cells
What is a somatic cell?
Cells in the body that are NOT sex cells e.g. cheek cells
What are gametes?
Reproduction or sex cells (sperm/eggs)
What does haploid mean?
The copy of each chromosome (46/2=23)
What is an autosome?
Any chromosome NOT involved in sex determination
What is a sex chromosome?
Chromosomes that determine a person’s sex
xy- male
xx- female
What is a pedigree chart?
A chart of genetic history over several generations
How do we determine if the disease is autosomal?
If it is 50/50 between males and females
How do we determine if the disease is X-linked?
If most males are affected by it
How do we determine if the disease is dominant?
One of the parents have to have it
How do we determine if the disease is recessive?
Neither parent have to have it, they can be heterozygous
What are the symbols for their genders?
Circle: female
Square: male
How can you tell if they are married?
It will have a line between them
How can you tell if they are siblings?
It will have a line at the top connecting them