Zusammenfassung der Ressource
Biology B23-24
- Characteristics
- Determined by...
- Genes
- Eye colour
- Nose shape
- Ear lobe shape
- The environment
- Scars
- Learning to speak a
language
- Genes and the environment
- Intelligence
- Height
- Body mass
- Chromosomes
- inside the nucleus of every cell
- Each body cell...
- 23 matching
pairs of
chromosomes
- 1 member of each pair
from dad-sperm
- 1 member of each pair
from mum-egg
- contain
genes
- Contain coded information
- The codes control different
characteristics of the body
- Reproduction
- Sexual reproduction
- different gametes
- Different sex cells
- Sperm-dad
- Egg-mum
- Each gamete-half the
number of chromosomes
- Female-egg
- 1 produced each month
- Male-Sperm
- Hundreds made each day
- Each sperm nucleus
contains 23
chromosomes
- Fertilisation
- One sperm will
fertilise one egg
- Two nuclei fuse
together
- The chromosomes from
each parent pair up
- The result is a new individual with
a mix of genetic information
- This is why offspring have genetic
variation
- Asexual reproduction
- Only one parent is needed
- No gametes
- No mixing of genetic
information
- No genetic variation
- Offspring are
genetically identical to
their parent
- Cuttings
- genetically identical plants
- Advantages
- Quick and cheap
- Genetically identical
to the parent
- Will have the parent's
desirable characteristics