The Living Environment
The passing of genetic information to offspring through reproduction
Genetic instructions passed onto offspring that determines traits and characteristics
things pass their genetic characteristics to their offspring.
contain the instructions to make different types of proteins, which are the building
blocks of all cells and organisms.
different types of a specific gene.
(ex) Blue eyes al
lele vs. Brown eyes allele.
(Deoxyribo Nucleic acid)
Molecules that carry genetic information.
Pairs of tightly wound packets of DNA located in the nucleus of
46 chromosomes (23 pairs)
6 chromosomes (3 pairs)
104 chromosomes (52 pairs)
METHODS OF REPRODUCTION
ONE parent produces an identical offspring (
exact genetic copy of itself
. (ex) Bacteria
TWO parents produce sex cells that carry genetic information of each parent
to create an offspring.
When sperm & egg co
mbine to form a unique organism.
(ex) In Humans
23 chromosomes Egg
23 chromosomes = Offspring 46 chromosomes
Between two parents, there is a possibility of 16,777,216 variations of offspring (
THE GENETIC CODE
enetic code of all organisms is chemically held in its DNA.
THE STRUCTURE OF DNA
Pg 41 fig 3
Twisted ladder shape
or sides are a
Sugar / Phosphate
or steps are
Pg 42 fig 3
Consists of a Sugar, a Phosphate and a base Pair
are coded messages for a specific gene trait
. (ex) A T
Code for an entire Humans can have 3 billion bases !
A always goes with T C G
G always goes with C T A
May determine Eye Color
pg. 42 fig 3
Involves the production of identical copies of
DNA to pass genetic information to offspring
The bases of DNA are held together by weak chemical bonds
Special enzymes break these bonds (unzipping them apart) into 2 strands
Both strands pair up with free
floating bases following A
T & C
G pairing rules
Two identical DNA sequence copies are formed.
PROTEINS and CELL FUNCTIONING
are formed by 20 kinds of amino acids in a
* The sequence of amino acids determines its
then determines the protein’s
(ex) Proteins can be hormones, enzymes, antibodies or different types of organs
PROTEINS DO MOST OF THE WORK IN CELLS
PROTEIN SYNTHESIS (Creation)
Cell organelles that make different types of proteins using instructions from DNA.
l enzyme molecules read DNA instructions in cell nucleus.
Special enzymes create a “messenger molecule”,
, to carry
through the cytoplasm to the Ribosome.
in cytoplasm and
assembles the protein
delivered A Acids
Any change in the DNA sequence which changes the genetic instructions, thereby causing
incorrect protein assembly.
Changing the base *
removing a base
adding a base
Reversing a base sequence
Mutated cells that don’t die can cause disease or deformities.
tions found in sex cells can be passed onto offspring.
DNA & INDIVIDUALITY
Every cell of an organism has a COMPLETE set of genetic instructions to
make an ENTIRE & EXACT organism. (Clone)
* Cells are different because only SOME of th
e entire genetic instructions become activated.
Genetic Activation can be Hormonal (ex) Puberty or Environmental (ex) Temperature change (Pg 46 fig 3
a genetic trait or characteristic
by hormones or environmental
deliberately altering the genetic instructions in an organism.
Applying technology to biological sciences (ex) Bread / Cheese
Adding microbes like yeast.
choosing to breed certain
plants and animals for desired traits (ex) Chicken / Cattle for less fat
naturally resistant to disease
using genetic engineering to produce better plants and animals
(ex) Plants containing gen
es that make chemicals harmful to insects but are harmless to humans.
Organisms like Bacteria that eat oil spills or that make insulin for diabetics.
How Genes are manipulated
Special enzymes are used to cut and splice specific
DNA gene segments to be attached to
a new organism.
Pg 47 Fig 3
Transplanted genes direct organism to make specific desired proteins that were made by original donor organism.
APPLICATIONS OF BIOTECHNOLOGY
By decoding the genes th
at cause disease, we can alter the sequence mutation and cure the disease.
Medicines can be made more effective.
Creating purer forms of missing chemicals is cheaper and safer than extracting chemicals from other organisms