1. DNA is found in the nucleus and contains the genetic instructions for making all the proteins in an organism. 2. DNA exists as double-stranded helix containing four nitrogen bases - adenine, guanine, cytosine, and thymine. 3. During cell division, the DNA duplicates itself so that each new cell contains identical genetic information as the parent cell.

2. 1. THE PRINCIPLE OF UNIT CHARACTER –
HEREDITARY CHARACTERISTICS ARE
CONTROLLED BY A PAIR FACTORS ( GENES IN
PAIR)
2. THE PRINCIPLE OF DOMINANCE AND
RECESSIVENESS – ONE FACTOR IN A PAIR
(DOMINANT) PREVENTS THE EXPRESSION OF
THE OTHER TRAIT( RECESSIVE)
3. THE PRINCIPLE OF SEGRAGATION – ONE AND
ONLY ONE MEMBER OF A PAIR OF FACTORS GOES
TO A GAMETE.

5. ROUND WRINKLED
GENOTYPE
RR rr 100% Rr
Rr Rr PHENOTYPE
100% ROUND
Rr Rr

8. S Y s y Ss Yy (self
fertilized
SsYy x SsYy

9. Checkpoints: Complete the table below.
ovum SY S Y s y s y
sperm
S
Y
S
Y
s
y
s
y

10. Genotype =

11. CATTLE
P₁ rr x ww --- rw ( roan) F₁
(red) ( white)
P₂ rw x rw --- ( red, Roan, white) F₂
GUMAMELA FLOWER
P₁ RR x WW --- RW ( PINK) F₁
P₂ RW x RW –---- RR, RW, WW (RED, PINK, WHITE) F₂

12. In a radish, long and round shapes are both dominant.
Find the genotypic ratio and phenotypic ratio of the
cross between ;
1. Long and round radish
2. oval and long radish
3. oval and round radish

13. A long strand of DNA
(deoxyribonucleic acid).
The stuff in your body that carries
information that makes you” you”.
The long strand of DNA gets coiled in your body cell
that during cell division, it ends up coiling by
forming 2 sisters chromatid joined together by
A centromere
Known as the
Chromosome.

14. The long strand of DNA in all our body cells, when unwrapped, it could make us travel
3000 times from the earth to the moon.
However, only 2 to 3 % of all the DNA actually codes for the traits inside
our bodies. Those important parts are the GENES.
GENES – a DNA
Segment sequences
That code for many gene
Different traits.
gene
junk

15. A DNA has a thousands of GENES.
An average gene has 10,000 to 15,000
Pairs of bases.
CHROMATID
CENTROMERE
CHROMATID
chromosome

16. Double helix strand DNA
adenine
Purine group
Cytosine
Pyramidine group
Guanine
Thymine

17. Nitrogen Nitrogen
base base
A T sugar
phophate
phophate
sugar
NUCLEOTIDE – simplest unit of
DNA

18. During cell division,
exact duplicates of
the chromosomes are
made so that the
genetic information
in the chromosomes
are passed to the
chromosomes of the
succeeding cells.
Provides the blueprint of all forms of life

19. Gets direction in making protein from the DNA

21.  Found in the nucleus,  Found in the nucleus
cytoplasm and  Deoxyribose for the
ribosomes sugar component
 Sugar component is  Double – stranded
ribose  Bases – ADENINE,
 Single strand GUANINE, CYTOSINE
 Nitrogen base- and THYMINE
ADENINE,GUANINE,CY  Directs protein synthesis
TOSINE and URACIL
 Involved in protein
synthesis

22. Double helix strand DNA
Adenine
Cytosine
Guanine
Thymine

23. RNA DNA
 Nucleus, cytoplasm and  ? NUCLEUS
Ribosome  Deoxyribose- sugar
 ? RIBOSE component
 Single strand  ? DOUBLE STRAND
 ? URACIL  Thymine – base
 Involved in protein  ? DIRECTS PROTEIN SYNTHESIS
synthesis