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BIOMOLECULES
Carbohydrate
Protein
Building
Block
Uses
Examples
Test
Simple
sugars
Ready source of
energy
Glucose
Glycogen
Cellulose
Starch
•
Enzymes (ase)
Hemoglobin
Antibodies
Protein
hormones
(insulin)
•
Reacts with
Biuret Solution
Fats, oils
•
Leaves oily spot
on brown paper
bag
DNA, RNA
•
DNA stains
(methylene blue)
Amino acids • Transport
•
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Lipid
Fatty Acids
•
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Nucleic Acid
Nucleotide
Speed up
reactions
Immunity
Cell
communication
Back up energy
source
In membrane
Store and transmit
genetic info
•
STARCH turns
purple in iodine
SUGARS react
with Benedict’s
Solution
CELLS
E U K A RYOTIC
P ROK A RYOTIC
•
•Prokaryotic cells have DNA and
ribosomes, but they have no
internal membranes! (They don't
have a nucleus)
•They have ribosomes to make
proteins
•These are the simplest cells
•Examples are bacteria, like
those that cause strep throat.
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Eukaryotic cells have their DNA surrounded by
a membrane. (They have a nucleus).
Two examples shown are plant cells and
animal cells, but fungi and protists are also
eukaryotic
Notice, plants have chloroplasts (for
photosynthesis) and cell walls made of
cellulose. Animal cells don't have these
parts. Also, plant cells have a larger vacuole
for storage.
Both plants and animals have mitochondria to
make ATP.
All eukaryotic cells have ribosomes to make
protein
These cells are more complex than prokaryotic
cells.
CELL MEMBRANE
• The plasma membrane surrounds
EVERY cell.
• It is made of lipid and protein
• It controls what goes in and out of a cell.
• Associated with HOMEOSTASIS
CELL TRANSPORT
Diffusion
Osmosis
Active
Transport
Movement from
high to low
concentration
Movement of water
from high to low
WATER
concentration
across a membrane
Movement from
LOW concentration
to HIGH
concentration
No energy required
No energy required
USES ATP
PHOTOSYNTHESIS AND RESPIRATION
CONVERTS SUNLIGHT TO
CHEMICAL ENERGY
CONVERTS ENERGY IN
FO O D (G LU C O S E ) TO AT P
Cellular Respiration
•Takes place in
mitochondrion
•Releases the energy
stored in glucose
•AKA aerobic respiration
(NEEDS oxygen)
AEROBIC VS ANAEROBIC RESPIRATION
A E RO B IC R E S PIR AT IO N
A N A E RO B IC R E S PIR AT IO N
•Does not use oxygen
•Makes only 2 ATP
•
Requires oxygen
•
Makes A LOT of ATP
•
Produces carbon
dioxide and water
• Also called fermentation
•
Happens in
mitochondrion
• Happens in cytoplasm (cytosol)
• Small amount of ATP
• YEASTS make ethyl alcohol
• BACTERIA and MUSCLE CELLS (w/o O2)
make LACTIC ACID
ATP CYCLE
CLICK THE ICON FOR SOUND
ASEXUAL VS SEXUAL REPRODUCTION
ASEXUAL REPRODUCTION
•Creates identical
copies (clones)
•Only involves MITOSIS
•ONE parent involved
•Common in bacteria
and unicellular protists
SEXUAL REPRODUCTION
•Adds genetic variation
•Involves meiosis and
fertilization
•TWO parents involved
•Diploid and haploid cells
MITOSIS AND MEIOSIS
MITOSIS
•One division
•2n  2n
• (same number of chromosomes)
•Results in 2 genetically identical cells
MEIOSIS
•Two divisions
•2n  n
• Half the number of chromosomes
•Results in 4 DIFFERENT haploid cells
•Forms gametes (egg and sperm)
DNA
•
DNA is a polymer of nucleotides.
• A nucleotide is made up of three parts: a sugar, a phosphate and one of four
bases
• In DNA, the bases are A, T, C, and G
•
DNA’s shape is a double helix
• The two strands are held together by HYDROGEN bonds
• A binds to T
• C binds with G
DNA REPLICATION
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Process of DNA copying itself
Steps
• DNA Unzips (Hydrogen bonds break)
• Each side acts as a template
• New DNA nucleotides are added according to base-pairing rules
• Two new molecules of DNA result – each with one old and one new
strand.
Happens in INTERPHASE (before mitosis or meiosis)
PROTEIN SYNTHESIS
•
Remember, genes are made of DNA and are in the nucleus
•
Genes (DNA) contain the instruction for making a protein
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In transcription, DNA is used to make mRNA in the nucleus
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mRNA then leaves the nucleus and goes to the ribosome
•
In translation, tRNA then brings amino acids in the proper order to make the
protein on the ribosome.
DNA  mRNA  protein
Made of amino acids
PROTEIN SYNTHESIS
DNA
RNA
PROTEIN
•DNA is in nucleus
•GENES (made of DNA) hold code for protein
•mRNA is made in nucleus
•TRANSCRIPTION
•Remember base pairing rules
•mRNA goes to ribosome
•3 bases on mRNA is a codon – each codon codes for one amino acid
•tRNA brings the right amino acid to the mRNA
•Anticodon on tRNA base pairs with codon on mRNA
CAN YOU IDENTIFY THE PARTS?
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
DNA
mRNA
Nucleus
Cytoplasm
Ribosome
Codon
Anticodon
tRNA
Amino acid
Protein (polypeptide)
READING THE CODON CHART
•
Be sure to use
mRNA
•
You won’t have to
memorize this!
•
What amino acid
is coded for by the
DNA
ATA GAG
First convert DNA to mRNA
ATA GAG
UAU CUC
UAU = tyr
CUC = Leu
GENETICS
We have two genes for each trait –
this is our GENOTYPE
One gene came from mom, one from
dad
If the genes are alike, the individual
is homozygous (RR, rr)
If the genes are different , they are
heterozygous (Rr)
Some genes are dominant and
others are recessive
We only show a recessive trait if we
have no dominant gene
RR and Rr would “look”
dominant
rr would look recessive
This diagram shows the cross
between 2 heterozygous purple
flowers
Cross is: Bb x
Bb
Notice that 75% are purple and 25%
white
SEX LINKAGE
Females are XX
Males are XY
Sex-linked traits are on
X chromosome
Trait is more common
in MALES
Examples are
colorblindness and
hemophilia (blood fails
to clot)
• Males give X chromosomes to
their daughters and Y’s to their
sons
• Moms give X’s to both daughters
and sons
CODOMINANCE – BLOOD TYPE
• Four blood types
 A, B, AB, O
Three different
alleles: A, B or
neither
A = AA or AO
B = BB or BO
AB = AB
O = OO
Agglutinogen
= protein
PEDIGREES
Tracing traits through generations
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Males are squares
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Females are circles
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Horizontal line means married
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Vertical line means children
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Filled in circle means the
individual HAS the condition
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Can you identify the genotypes
of individuals 4, 7, 12?
4 = Ee (parent 2 had to give an e)
7 = Ee (child is ee, so they had to have one e)
12 = ee (affected with recessive condition)
XY = male
3 21’s =
Down
Syndrome
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In humans, 22 pair of autosomes
1 pair of sex chromosomes
XX = female
XY = male
Extra chromosomes a result of
non-disjunction
• Chromosome pairs fail to separate in meiosis
• One example is DOWN SYNDROME (extra 21)
• Another example is KLINEFELTERS (XXY)
GENETIC TECHNOLOGY
DNA FINGERPRINTING
TRANSGENIC ORGANISMS
•Gene cloning
•Use gel
electrophoresis to
compare DNA
fragments
•Uses bacteria to make
human proteins like
insulin
•IF DNA matches, it’s
from the same
individual
•Organisms that have 2
different kinds of DNA
Evidence points
to suspect 2
EVOLUTION – CHANGE OVER TIME
EVIDENCE
N AT U R A L S E LE C T IO N
•Fossil evidence
•Credited to Charles Darwin
• Fossils found in sedimentary
rock
• Lower level fossils are older
and more PRIMITIVE
• We can compare fossils to
modern organisms
• Similar structure suggests
common ancestor
•Biochemical evidence
• DNA and protein similarities
suggest common ancestor
• Organisms in populations have
variations that can be passed
from generation to generation
• More organisms born that
environment can support
• Organisms compete for
resources
• Those organisms with
favorable variations have more
babies and the population
evolves