this powerpoint review genetics for the living environment regents exam.

2. Ever since hominids evolved into
humans, they have observed that
organisms resemble their blood relatives!

3. For most of human history, people did
not know conclusively WHY people
resembled their families!

4. The work of many, many, many people
(Mendel, Hershey, Chase, Avery, Watson, Crick et al)
over many, many, many years led to the
determination that DNA is why organisms resemble
their relatives.
You mean I
resemble you
because I have
your DNA?
EWW! GROSS!

5. The following is what you must know about
genetics
(the study of genes, DNA and heredity)….

6. ….

7. the thread-like
structures called …

8. many ….

9. for example: a human cell has many
thousands of genes.

11. (how we look)
Hey pop, we
share the
same recipes! I’ll alert the
media.

12. Make an inference about these men’s
genes.

13. Is it obvious that these men MUST share
some of the same genes…because they
share physical traits?

15. Organisms with very similar DNA
sequences are related

17. In there is only
.

18. In there is only
.

20. : the
( cell), the ( ).
. The
and is NOT identical to
either.

23. Due to gene recombination during fertilization no
two offspring are exactly identical.

24. huge amount of
( )
Same parents
but none are
exactly
identical!
Sexual
reproduction
at work!

25. Karishma & Kareena Kapoor (Bollywood actresses) have the same
mother & father but don’t resemble each other!
Crossing over & gene recombination at work!
Me cuter
than she!

26. Now answer# 1-12

28. The molecule
(the recipes from making a
particular life-form)
Resembles a
double
twisted
ladder.

29. (nitrogen bases)
the letters:

30. ONLY .
ONLY (in DNA).

31. Fill in the blanks!

32. A-T, C-G!
A A
G T

33. Fill in the blanks!

34. Fill in the blanks!
G
A
T

35. (the recipe) for
telling a cell what to do.

37. If the sequence of nucleotide bases in DNA
is changed. The change in the DNA causes
a change in the organism’s genes.
This is called a .

38. :a

39. A mutation changes an organism’s recipe
Oops!

40. some mutations are harmless, What am I going
to do? My future
in-laws will be
others are very bad! here any
minute!
It’s a
little
crispy

41. Who could have Once in a while a mutation
guessed that
they’d like confers a genetic advantage!
soup and ice
We were
cream!!!!
original!

42. A mutation can happen in ANY body
cell. a mutation can make a cell
cancerous!
Cancer: an
uncontrolled
growth &
division of
cells. Caused
by a mutation
in the DNA of
just one cell!
The mutated
cell passes its
bad genes as

43. Although a mutation can happen in ANY
body cell,
.

44. Peter parker gained his powers
from a radioactive spider. His
powers could only be passed to
his offspring, IF the mutation
were encoded in his gametes
(sex cells).

45. (mutation-causing agents):

48. This picture has been on several
regents exams…

49. What is mutation A?

50. What is mutation A? a

51. What is mutation B?

52. What is mutation B?

53. What is mutation C?

54. What is mutation C?

55. sickle cell anemia is the result of single
mutation

56. Now answer #13- 39.

57. DNA replication:

58. DNA replicates by semi-
conservative replication.

60. The central dogma
of genetics
(How DNA makes us who we are)

61. The central dogma of genetics:
.

62. .

63. Step 1: DNA gives instruction to mRNA on
how to make a protein.

64. Step 2: mRNA leaves the nucleus & takes
the instructions on how to make a protein
to ribosomes (the cell’s protein factories).

65. Step 3: the ribosomes, use instructions to
have tRNA bring the correct amino acids.

66. Step 4: the ribosomes bond the correct
amino acids (in peptide bonds) to form a
specific protein.

67. The sequence of amino acid gives the
protein its particular shape…

68. The protein’s shape gives the protein its
function

69. The protein’s function give the organism
its trait.

70. This is the Universal Genetic Code Chart…it
shows the messenger RNA codes and the
Amino Acids they code for.

71. The three letter codons with the
A’s, U’s, C’s and G’s, (such as UCU, or GAU
etc) are the mRNA segments….

72. The “PHE”, “LEU”, “SER” ETC are the
amino acids….

73. “PHE” is the amino acid phenylalanine
“LEU” is leucine “SER” is serine etc

74. You must be able to use this chart:

75. Examples:

76. What does the
codon: code for?

77. What does the
codon: code for?

78. What does the
codon: code for?

79. What does the
codon: code for?

80. The chart is like a translation of two
different languages (mRNA’s language &
Amino Acid’s language)

81. The following is how the genetic code in
DNA becomes an amino acid:

82. 1. : . Since it CAN’T
leave the nucleus, DNA essenger . DNA only
speaks “DNA language”. mRNA transcribes (writes down) the recipe but
in the language of RNA!
We need to
make some We would like to
Yes, sir. one
proteins. make a protein. the
coming
Order for recipe is : , can the
right up!
me! chef make it?
Messenger
RNA
chromosomes What’s
of DNA GUG is
GUG? I what I
ASKED for call CAC,
CAC! sir

83. 2. the and
the the (the
Hey Chef protein factories)
Ribosome!
we have a special
customer order!
The recipe is .
Do you have the
ingredients to
make it? No
mRNA Problem!

84. 3. : the , the ribosomes
the and tells tRNA to get the
correct protein.
mRNA Hey tRNA, the
said . customer is waiting!
That’s Please get me some
! asap!
Right away, chef
ribosomes! is
right?
Ribosome:
the protein chef
Yes!

85. Finally
Here’s
your Looks
VAL, the delicious!
ribosome
says to
enjoy!
Just what
we
wanted!

86. Remember this picture it show
transcription

87. Now answer 40-55

88. Gene expression:

89. All the cells in an organism’s body have
the exact same genes. But, Different
cells of the body use different genes

90. the Different cells of an organism’s body
EXPRESSES different genes but contain all
the same DNA.
Skin cells express
the skin genes.
The eye cells
express the eye
genes.
The muscle cells
express muscle
genes.

91. the Different cells of an organism’s
body EXPRESSES different genes but
contain the same DNA.

92. the Different cells of an organism’s
body EXPRESSES different genes but
contain the same DNA.

93. the Different cells of an organism’s
body EXPRESSES different genes but
contain the same DNA.

94. WHY don’t cells use EVERY gene? Because
it would to express
genes that they don’t to use!

95. Environment
effects gene
expression.

96. The environment can influence which
genes are expressed

97. Some animals’ fur changes color when the
seasons change.

98. Why might seasonal color change be a
useful adaptation?

99. seasonal color change is a useful
adaptation because they can camouflage
(hide) from predators

100. This white rabbit’s fur can turn black, where an ice
pack is placed on his white fur because: the
environment can influence which genes are expressed

101. These leaves are from the same tree but look very
different because: the environment can influence
which genes are expressed
I have to
be large
to get
light
I don’t have
because
to be large,
there is
because I
very
get plenty
little
of light
sunlight
where I
grow

102. Green grass turns yellow when it doesn’t get any sunlight but
turns green again if given sunlight because: the environment
can influence which gene expressed

103. These 61 year olds are genetically identical twins but look
very different. because: the environment can influence which
I look “mad genes are expressed I never
old” because I smoked, dran
smoked, drank k or
alcohol and suntanned!
suntanned all
my life

104. Now answer 56- 75

105. Biotechnology: selective
breeding & genetic engineering

106. Humans have learned to use
organisms’ genes to benefit
humankind.
This is called
biotechnology
.

107. The two types of biotechnology are
•Selective breeding
•Genetic
engineering

108. Selective breeding means:
Selecting one plant ( or
animal) with a desirable
characteristic and
breeding it with another
plant (or animal) with a
different desirable trait, to
hopefully get a hybrid
offspring with BOTH
desirable traits.

109. Humans used selective breeding to
create FIVE different vegetables from
wild mustard….

110. Humans have selectively bred
hundreds of dog breeds

111. All the plants and all the animals that
humans interact with have been
selectively bred by people.

112. When selective breeding works, it
produces new species beneficial to
man….BUT, there are disadvantages…

113. selective breeding is expensive, time-
consuming and there is no guarantee that
offspring will have the desired traits.

114. Selectively bred species might have
abnormalities
Down syndrome?
Sterile, disease-prone

115. Now # answer 76-84.

116. Genetic
engineering:

117. Is this creature possible?
Spiderdog!, spiderd
og!
Does whatever a
spider can!

118. Humans have learned to use enzymes to
combine the DNA of UNRELATED species, it is
called: Genetic engineering
I’m the
REAL
spiderman!

119. How genetic engineering works:

120. 1. Scientists discover a desirable trait
in an organism…

121. 2. They identify the gene (the segment
of DNA that carries the trait)

122. 3. The gene is cut out of the original
organism’s DNA using enzymes

123. 4. The gene is pasted into a new
organism’s DNA using enzymes

124. 5. The new organism is now able to make whatever
protein is encoded in the recombined DNA.

125. Before the late 1970’s, diabetics were given
sheep insulin, BUT some diabetics were
allergic to the sheep antigens in sheep
insulin

126. Today, Gene recombination is how
insulin for diabetics is made.

127. The human insulin gene is inserted into a
bacterial DNA using enzymes. The bacteria
get reprogrammed to make human insulin.

128. Why bacteria? Bacteria are relatively easy
to transform, easy to grow, can produce
billions & billions of copies quickly and its
easy to purify the insulin.

129. Remember this picture: it shows
genetic engineering.

130. Remember this picture: it shows
genetic engineering.

131. Remember this picture: it shows
genetic engineering.

132. Remember this picture: it shows
genetic engineering.

133. Besides insulin, HGH, steroids
hormones like testosterone and
estrogen are also made through
genetic engineering.

134. Clearly, biotechnology shows great
promise to benefit mankind…
But there are ethical considerations
with gene recombination

135. 1818 Mary Shelley wrote “Frankenstein” about
about monster (a new life-form) made from bodies
sewn together…the story frightened some people,
others thought it was impossible…

136. Today, scientists are learning to
surpass Dr. Frankenstein
The following pictures are fake, but
for how long?

146. Now answer
#85- 101