Date: Dec 2, 2024
Intro to Genetics
Genotype: Genetic makeup
Phenotype: the physical manifestation of their genetic make-up.
Chromosomes: made of DNA and protein. It exists in either single stranded form OR double
stranded form (ie. following a replication process). It consists of a specific sequence of genes
that each code for a specific polypeptide sequence. Each chromosome has a distinct size, a
specific short arm, long arm length, a unique gene count and sequence and a specific
centromere location. There are 46 Chromosomes in one person (23 from mom, 23 from dad)
Karyotype: depicts all of the chromosomes of an individual and pairs them up based on their
size, length of their short arm and long arms, location of their centromere and the gene
sequence each contains. Depicted to the side is the karyotype of a normal human with 46
chromosomes arranged in 23 pairs, arranged largest to smallest, with one of them being sex
chromosomes (determining gender).
DNA: two long strands made up of repeating sequences of simple units called nucleotides (or
bases). The nucleotide sequences in the two strands run in opposite directions to each other,
which is why we describe the molecule as anti-parallel.
Nucleotide: monomer of Nucleic Acids. consist of a nitrogen
base (bonded by a glycosidic linkage), a five-carbon sugar
(deoxyribose for DNA and ribose for RNA),and a phosphate
group (bonded by a phosphodiester linkage).
Purines: have a double ring structure – A G
Pyrimidines: have a single ring structure – C T
(A-T) – 2 H bonds while (G-C) – 3 H bonds
Chemical Composition of DNA
- long strands of repeating units (nucleotides)
- nucleotides consist of five-carbon sugar, nitrogen base (A, C, G, T), phosphate group
- strands run in opposite (anti-parallel) directions
Sugar-Phosphate linkage: forms the backbone of the DNA molecule.
5’ and 3’ ends: two ends of DNA strands. Nucleotide sequences are always read from the 5’ end
to the 3’ end.
Spiral or Double Helix Shape: most stable configuration as DNA will be long as a ladder and due
to bond angles and lots of hydrogen bonds
Cell Cycle
Cell Theory:
a. All living organisms consist of one or more cells
b. The cell is the basic unit of structure for all living organisms.
, Date: Dec 2, 2024
c. Cells arise from pre-existing cells
Cell Cycle: is the series of events that allows a cell to prepare for and complete cellular division
Cell Division: is the process by which one cell (parental cell) gives rise to 2 genetically identical
daughter cells… only difference is daughter cells initially are smaller than parent cells. Involves
a single duplication of genetic material followed by a single division of all cellular components.
fulfills three main functions which include: Overall, cell division …
- Healing and tissue repair - increases cell count
- Growth (of organism) - increases organism size
- increases complexity of organism
- Cellular Reproduction
1. Growth: continued cell division contributed to further growth of organism from single
cell to trillions of cells
2. Healing and Tissue Repair: Cells are continually needing repair – UV, time, etc. can kill or
damage cells – outer (epidermal) layer of skin is dead cells that dry and are sloughed off
∴ must be replaced. Without cell division to replace these cells, organisms would shrink
in size and eventually die (ie: showering, sunburn, etc).
3. Cellular Reproduction: Cell division also perpetuates life cell division in some unicellular
organisms and gives rise to two new organisms (binary fission in bacterial cells). – Cell
cycle in eukaryotes generates new cells (ie. cellular reproduction)
OVERALL…the CELL CYCLE ensures that each and every SOMATIC CELL comprising an organism
has the exact same genetic info as the original zygomatic cell produced at conception!
Interphase: the sequence of events leading up to cell division in
which all necessary preparations are made – the time between
active divisions and comprises the majority of a typical cell cycle!
Mitosis and Cytokinesis: the actual cellular division process in
which a single parent cell gives rise to 2 daughter cells identical to
itself and each other in all respects except size (daughter cells are
smaller than parent cell)
Actual Cellular Division Phase: cytokinesis begins before mitosis is complete
Mitosis: the division of nuclear materials that were previously duplicated in interphase.
Cytokinesis: the separation of the cytoplasm and its contents into equal parts.
In animal cells, the membrane pinches in to separate cytoplasm, while in plant cells a new cell wall forms
along the middle to create two new cells.
During interphase (defined as the stage between cell divisions)… the cell appears to be at rest
microscopically but actually is busy preparing for division
Intro to Genetics
Genotype: Genetic makeup
Phenotype: the physical manifestation of their genetic make-up.
Chromosomes: made of DNA and protein. It exists in either single stranded form OR double
stranded form (ie. following a replication process). It consists of a specific sequence of genes
that each code for a specific polypeptide sequence. Each chromosome has a distinct size, a
specific short arm, long arm length, a unique gene count and sequence and a specific
centromere location. There are 46 Chromosomes in one person (23 from mom, 23 from dad)
Karyotype: depicts all of the chromosomes of an individual and pairs them up based on their
size, length of their short arm and long arms, location of their centromere and the gene
sequence each contains. Depicted to the side is the karyotype of a normal human with 46
chromosomes arranged in 23 pairs, arranged largest to smallest, with one of them being sex
chromosomes (determining gender).
DNA: two long strands made up of repeating sequences of simple units called nucleotides (or
bases). The nucleotide sequences in the two strands run in opposite directions to each other,
which is why we describe the molecule as anti-parallel.
Nucleotide: monomer of Nucleic Acids. consist of a nitrogen
base (bonded by a glycosidic linkage), a five-carbon sugar
(deoxyribose for DNA and ribose for RNA),and a phosphate
group (bonded by a phosphodiester linkage).
Purines: have a double ring structure – A G
Pyrimidines: have a single ring structure – C T
(A-T) – 2 H bonds while (G-C) – 3 H bonds
Chemical Composition of DNA
- long strands of repeating units (nucleotides)
- nucleotides consist of five-carbon sugar, nitrogen base (A, C, G, T), phosphate group
- strands run in opposite (anti-parallel) directions
Sugar-Phosphate linkage: forms the backbone of the DNA molecule.
5’ and 3’ ends: two ends of DNA strands. Nucleotide sequences are always read from the 5’ end
to the 3’ end.
Spiral or Double Helix Shape: most stable configuration as DNA will be long as a ladder and due
to bond angles and lots of hydrogen bonds
Cell Cycle
Cell Theory:
a. All living organisms consist of one or more cells
b. The cell is the basic unit of structure for all living organisms.
, Date: Dec 2, 2024
c. Cells arise from pre-existing cells
Cell Cycle: is the series of events that allows a cell to prepare for and complete cellular division
Cell Division: is the process by which one cell (parental cell) gives rise to 2 genetically identical
daughter cells… only difference is daughter cells initially are smaller than parent cells. Involves
a single duplication of genetic material followed by a single division of all cellular components.
fulfills three main functions which include: Overall, cell division …
- Healing and tissue repair - increases cell count
- Growth (of organism) - increases organism size
- increases complexity of organism
- Cellular Reproduction
1. Growth: continued cell division contributed to further growth of organism from single
cell to trillions of cells
2. Healing and Tissue Repair: Cells are continually needing repair – UV, time, etc. can kill or
damage cells – outer (epidermal) layer of skin is dead cells that dry and are sloughed off
∴ must be replaced. Without cell division to replace these cells, organisms would shrink
in size and eventually die (ie: showering, sunburn, etc).
3. Cellular Reproduction: Cell division also perpetuates life cell division in some unicellular
organisms and gives rise to two new organisms (binary fission in bacterial cells). – Cell
cycle in eukaryotes generates new cells (ie. cellular reproduction)
OVERALL…the CELL CYCLE ensures that each and every SOMATIC CELL comprising an organism
has the exact same genetic info as the original zygomatic cell produced at conception!
Interphase: the sequence of events leading up to cell division in
which all necessary preparations are made – the time between
active divisions and comprises the majority of a typical cell cycle!
Mitosis and Cytokinesis: the actual cellular division process in
which a single parent cell gives rise to 2 daughter cells identical to
itself and each other in all respects except size (daughter cells are
smaller than parent cell)
Actual Cellular Division Phase: cytokinesis begins before mitosis is complete
Mitosis: the division of nuclear materials that were previously duplicated in interphase.
Cytokinesis: the separation of the cytoplasm and its contents into equal parts.
In animal cells, the membrane pinches in to separate cytoplasm, while in plant cells a new cell wall forms
along the middle to create two new cells.
During interphase (defined as the stage between cell divisions)… the cell appears to be at rest
microscopically but actually is busy preparing for division
