1. Cellular Reproduction and DNA
Offspring receive their traits from their parents- but sometimes the child looks nothing like the parents 1 1

2. Cellular Reproduction and DNA
Offspring receive their traits from their parents- but sometimes the child looks nothing like the parents
Lamarkian biology- characteristics such as height, strength, and weight are determined by the activities of the parents. (FAIL.) 2 2

3. The Father of Modern Genetics
Gregor Mendel ( ): an Austrian monk
Gave first real explanation for how traits are passed on to offspring
Conducted meticulous experiments on 29,000 pea plants
Mendel's work was rejected during his lifetime, and it wasn't widely accepted until the 1930's and 1940's
Genetics- the science that studies how characteristics get passed from parent to offspring 3 3

4. Genes, Chromosomes, and DNA
DNA governs an organism's traits and characteristics
DNA's main function is to tell the cell what proteins to make 4 4

5. Genes, Chromosomes, and DNA
DNA governs an organism's traits and characteristics
DNA's main function is to tell the cell what proteins to make
Not every organism's traits are completely determined by a person's genes
Genetic tendency- a range of possible characteristics set by DNA 5 5

6. Genetic Tendencies
People have a certain capacity for musical ability, or athletic ability
Some people choose to fight against genetic predispositions such as alcoholism and obesity
Consider an alcoholic whose father is also an alcoholic- you could argue that the son learned this through father, or that alcoholism is in his genes, or it's a combination of both 6 6

7. Genetic Tendencies
People have a certain capacity for musical ability, or athletic ability
Some people choose to fight against genetic predispositions such as alcoholism and obesity
Consider an alcoholic whose father is also an alcoholic- you could argue that the son learned this through father, or that alcoholism is in his genes, or it's a combination of both
Gay rights activists are searching for a “gay gene” in order to justify their behavior
However, many defects are transmitted through genes (eg. Down Syndrome, cystic fibrosis, color blindness)
Even if a “gay gene” were found, a gene cannot force a person into a homosexual lifestyle- he is able to choose how to live, just like an alcoholic can choose not to drink alcohol 7 7

8. Developmental Factors
Characteristics completely from DNA: hair color, blood type
DNA alone does not determine who you are or what you will become
DNA provides the general framework within which you decide who you will become 8 8

9. Developmental Factors
Characteristics completely from DNA: hair color, blood type
DNA alone does not determine who you are or what you will become
DNA provides the general framework within which you decide who you will become
Genetic factors- traits determined by DNA
Environmental factors- nonbiological factors that are involved in a person's surroundings (family, friends, school, choices they make)
Spiritual factors- factors in a person's life determined by the quality of their relationship with God
There is still much debate over how much influence each of these factors has over a person's development 9 9

10. Genes and DNA
Gene- a section of DNA that codes for the production or portion of protein, thereby causing a trait 10 10

11. Genes and DNA
Gene- a section of DNA that codes for the production or portion of protein, thereby causing a trait
The tasks that a cell can complete depend upon the proteins it produces
If a cell produces certain proteins, it's a nerve cell, if it make other proteins, it's a blood cell 11 11

12. Genes and DNA
Gene- a section of DNA that codes for the production or portion of protein, thereby causing a trait
The tasks that a cell can complete depend upon the proteins it produces
If a cell produces certain proteins, it's a nerve cell, if it make other proteins, it's a blood cell
A cell knows what proteins it should produce because the DNA tells it what to make 12 12

13. DNA and RNA 13 13

14. DNA and RNA DNA RNA Sugar: deoxyribose Structure: double helix
Nucleotides: adenine, guanine, cytosine, thymine
More stable, less likely to experience changes during duplication (less mutations)
RNA
Sugar: ribose
Structure: single strand
Nucleotides: adenine, guanine, cytosine, thymine
Less stable 14 14

15. Protein Synthesis- Part 1: Transcription
1. Transcription- building an RNA strand from a section of DNA
RNA copies DNA by attaching corresponding nucleotide bases
RNA is like a camera that produces a negative image (light in places it should be dark)
T- A
C- G
A- U 15 15

16. Protein Synthesis- Part II: Translation
2. Translation: the process of translating the nucleotide bases into amino acid sequences 16 16

17. Protein Synthesis- Part II: Translation
2. Translation: the process of translating the nucleotide bases into amino acid sequences
Messenger RNA (mRNA)- RNA that performs transcription and then goes to the ribosomes 17 17

18. Protein Synthesis- Part II: Translation
2. Translation: the process of translating the nucleotide bases into amino acid sequences
Messenger RNA (mRNA)- RNA that performs transcription and then goes to the ribosomes
Transfer RNA (tRNA)- contains an anticodon bonded to an amino acid
Anticodon- three nucleotide base sequence on tRNA 18 18

19. Protein Synthesis- Part II: Translation
Codon- a sequence of three nucleotide bases on mRNA that refers to specific amino acid 19 19

20. Protein Synthesis- Part II: Translation
Codon- a sequence of three nucleotide bases on mRNA that refers to specific amino acid
Translation repeats until all amino acids that are called for by codons are linked together
DNA → RNA → protein 20 20

21. Protein Synthesis- Part II: Translation
Codon- a sequence of three nucleotide bases on mRNA that refers to specific amino acid
Translation repeats until all amino acids that are called for by codons are linked together
DNA → RNA → protein
A given amino acid can be “called for” by several different codons. eg. cysteine can be called by UGC or UGU
However, a single codon cannot call for more than one amino acid (eg. UGU is only for cysteine)
Protein Synthesis 21 21

22. DNA and RNA Exons- part of DNA with instructions for making a protein
Introns- separates exons, must be removed before it becomes mRNA 22 22

23. DNA and RNA Exons- part of DNA with instructions for making a protein
Introns- separates exons, must be removed before it becomes mRNA
Introns are also known as “junk DNA” because they don't appear to serve any purpose
DNA is very thin mm
If all the DNA from one cell we strung together end to end, it would be six feet long. All DNA in body: 67 billion miles (16x distance of Pluto to Sun) 23 23

24. How DNA is Packaged
Histones- proteins that act as spools which wind up small stretches of DNA
Nucleosomes- beads of DNA wrapped around histone 24 24

25. How DNA is Packaged
Histones- proteins that act as spools which wind up small stretches of DNA
Nucleosomes- beads of DNA wrapped around histone
Chromosome- network of DNA coils and proteins
In nucleus 25 25

26. How DNA is Packaged
Histones- proteins that act as spools which wind up small stretches of DNA
Nucleosomes- beads of DNA wrapped around histone
Chromosome- network of DNA coils and proteins
In nucleus
Chromatin- strands of chromosomes, RNA, and proteins
Condensed chromosome- most compact version of DNA
Humans: 46 chromosomes horse: 64, crayfish: 200 26 26

27. Mitosis and Interphase
Mitosis- a process of asexual reproduction in eukaryotic cells
Interphase- time interval between cellular reproduction
Chromosomes not condensed
Cell spends most of its time in this stage
DNA remains in its chromatin form, except when making proteins
Cell cycle- cycle between interphase and mitosis 27 27

28. Mitosis In order to reproduce, chromosomes must duplicate
Sister chromatids- duplicate chromosomes
The centrioles also duplicate, then mitosis starts

29. -duplicated chromosomes coil into their condensed form
1. Prophase
-duplicated chromosomes coil into their condensed form
Centromere- the region that joins two sister chromatids
-aster- microtubules extended from centrioles
-as centrioles migrate, the microtubules grow, producing spindle fibers
- Spindle fibers make up the mitotic spindle 29

30. -chromosomes are lined up along equatorial plane
2. Metaphase
-chromosomes are lined up along equatorial plane 30

31. -chromosomes are lined up along equatorial plane 3. Anaphase
2. Metaphase
-chromosomes are lined up along equatorial plane
3. Anaphase
-microtubules separate the sister chromatids from each other
-sister chromatids are pulled to opposite sides 31

32. -chromosomes are lined up along equatorial plane 3. Anaphase
2. Metaphase
-chromosomes are lined up along equatorial plane
3. Anaphase
-microtubules separate the sister chromatids from each other
-sister chromatids are pulled to opposite sides
4. Telophase
-spindle begins to disintergrate
-plasma membrane begins to constrict along equatorial plane 32

33. -spindle begins to disintergrate
4. Telophase
-spindle begins to disintergrate
-plasma membrane begins to constrict along equatorial plane
-two cells begin to form
-nuclear membrane forms around each chromosome
- chromosomes uncoil from their condensed form back into chromatin
-the end result is two identical daughter cells 33

34. More About Mitosis
Each daughter cell gets at least one of each organelle
If the two cells have only one organelle between them, the organelle is split
DNA can build up or make new organelles as needed
The mitochondria has its own DNA so it can replicate itself 34

35. More About Mitosis
Each daughter cell gets at least one of each organelle
If the two cells have only one organelle between them, the organelle is split
DNA can build up or make new organelles as needed
The mitochondria has its own DNA so it can replicate itself
Mitosis is a form of asexual reproduction
Every eukaryotic organism performs mitosis
Mitosis produces new cells as the organism grows, and replaces dead cells
Millions of red blood cells die every minute 35

36. More About Mitosis
Plant mitosis: due to cell wall, the plasma membrane can’t constrict
Cellulose is formed in the middle, producing the cell well
Also no centrioles are in the plant cells 36

37. Chromosomes
Karyotype- the figure produced when chromosomes of a species during metaphase are arranged according to their homologous pairs
Homologous pairs- chromosomes that are very similar but not identical
Sex chromosomes- a pair of chromosomes which can be used to distinguish between the sexes
XX: female
XY: male

38. Diploid and Haploid Cells
each homologue has exactly the same number of genes as its partner
For example, the gene for blood type can be found on chromosome #9- on one homologue, the gene might be for blood type A and on the other, O.
Diploid cell- a cell with chromosomes that come in homologous pairs
Haploid cell- a cell that has only one representative of each pair 38

39. Diploid and Haploid Cells
Even species that have diploid cells will have some haploid cells
Diploid number (2n)- total number of chromosomes in a diploid cell
46 for human
Haploid number- (n) number of homologous pairs in a diploid cell
23 for human 39

40. Sexual Reproduction
Meiosis – the process by which a diploid (2n) cell forms gametes (n)
-each parent contributes 23 chromosomes
In meiosis, diploid cells get split into haploid cells called gametes
Gametes- haploid cells produced by diploid cells for purpose of sexual reproduction
Female: egg (ovum) Male: sperm
Two gametes join together to form a| diploid cell that has 23 homologous pairs of chromosomes- zygote

41. Meiosis I Meiosis I- one diploid cell forms two haploid cells
-two begin meiosis, cell must duplicate DNA and centrioles
Prophase I- centrioles move to opposite sides of cell
DNA is exchanged between homologous chromosomes (cross over)
Mitotic spindle forms
Metaphase I- single microtubule for each pair- chromatids stay intact

42. Meiosis I
Anaphase I- homologous pairs are pulled to either side Telophase I- plasma membrane constricts along equatorial plane -two haploid cells are formed -though each cell has 46 chromosomes, the cells are considered haploid because the chromosomes are paired with an exact duplicate, leaving 23 unique chromosomes

43. Meiosis
Prophase II- both cells have their centrioles duplicate and form a spindle Metaphase II- chromosomes line up along equatorial plane -chromosomes attach to each chromatid Anaphase II- the microtubules pull the chromosomes away from their duplicates Telophase II- plasma membrane constricts along equatorial plane, forming two pairs of haploid cells

44. Mitosis vs. Meiosis
Mitosis: one diploid cell forms two duplicate diploid cells
Meiosis: diploid to haploid
-One diploid cell forms 4 haploid cells 44

45. Spermatogenesis -In males, meiosis produces sperm cells
- At the end of meiosis II, flagella emerges on each of the four haploid cells 45

46. Oogenesis Oogenesis: meiosis in females
-at the end of telophase I, one of the two cells produced takes most of the cytoplasm and organelles
-After meiosis II, one of the big cells from Meiosis I takes most of the cytoplasm and organelles
-the end result is one large gamete (Egg cell) and three smaller polar bodies
- when the sperm burrows into the egg, it forms a diploid cell called a zygote 46

47. Viruses
Virus- non-cellular infectious agent 1. has genetic material (RNA or DNA) inside a protective protein coat 2. cannot reproduce on its own -a virus hijacks a cell in order to reproduce -because a virus cannot reproduce on its own, it’s not alive

48. Lytic Pathway Virus attaches to bacterium
Virus injects own genetic material
Virus DNA instructs bacteria to make viral proteins and genetic material
Viruses form in cell
Cell ruptures, releasing several viruses

49. Viruses
Some viruses, like HIV, can inject genes into the cell and lie dormant for several years before the lytic pathway starts
Viruses: chicken pox, flu, mumps, cold, mumps, measles, AIDS, cold sores, some forms of cancer
Viruses affect plants, animals, and bacteria

50. The Immune System
Phagocytic cells- purpose is to engulf and destroy pathogens (eg. White blood cells) Lymph nodes- a place for phagocytic cells to gather -lymph carries pathogens through the lymph nodes, where the phagocytic cells destroy them Antibodies- specialized proteins that aid in destroying infectious agents

51. Antibodies
-some antibodies can destroy many kinds of pathogens, others can only fight one kind -when the body is infected, it produces antibodies that will destroy the pathogen -the body remembers which antibodies will fight a particular disease Vaccine- a weakened or inactive version of a pathogen that stimulates the body’s production of antibodies which can aid in destroying a pathogen