Genetics and Evolution Flashcards
testes
Making sperm and are also involved in producing a hormone called testosterone
scrotum
Protecting the testes
Sperm ducts
To move sperm away from its storage place in the testicle
Prostate gland
Produce the fluid that nourishes and transports sperm (seminal fluid).
Urethra
Allows urine to pass outside the body
Penis
Urination and sexual intercourse.
Ovaries
Produce eggs for fertilization
Oviduct (fallopian tubes)
Passageway for an egg and a sperm to meet and for a fertilized egg (embryo)
Uterus
Menstruation and fertility
Cervix
Allows fluids to flow inside and out of your uterus
Vagina
Provides a passageway for blood and mucosal tissue from the uterus during a woman’s monthly period
What are gametes?
Reproductive cell
What happens during fertilisation
Sperm and egg unite in one of the fallopian tubes to form a zygote
zygote
Fertilized egg
embryo
The earliest development stage, which occurs after fertilization but before a foetus
foetus
The last stage of pregnancy
Haploid cells
One set of chromosomes (23 )
Diploid cells
Two sets of chromosomes (46)
Link between chromosomes - DNA - genes
DNA, genes and chromosomes work together to make you who you are
Location of DNA/genes in a cell
Cell nucleus
Description of DNA
Molecule that carries genetic information
made up of four base pairs (A+T and C+G)
Double helix
What is a human genome?
Total amount of genetic information
The importance of DNA making exact copies of itself
Ensures that when a cell divides, the offspring will receive the same genetic information as the parent cell.
Mutation
Change in genetic code
Examples of mutations
Cystic fibrosis, haemophilia, and sickle cell disease
Cause of mutations?
Radiation (UV light, gamma rays), accidental DNA damage, chemicals.(vaping or smoking)
Difference between dominant and recessive genes / alleles
Dominant allele= Expressed even when paired with recessive allele
Recessive allele=only visible when paired with another recessive allele.
genotype
Gene responsible for the characteristics of an individual (hair colour, eye colour)
phenotype
The physical characteristics of an individual (brown hair, blue eyes)
Discrete variation
Variations inherited and are usually controlled by one pair of genes (one allele from mum and one from dad)
i.e. height, skin colour etc
Continuous variation
Controlled by one gene and is distinct
i.e. rolling your tongue
mitosis
Cell division responsible for repair and growth
meiosis
Cell division, responsible for producing sperm and egg cells.
evolution
Explains how living things have changed over time and how they have come to be the way they are now.
What is selective breeding?
Choosing the parents with particular characteristics to produce offspring with more desirable characteristics.
Define the term fitness in the context of natural selection
More likely to survive and reproduce