Biology EOC Review

1. Biology EOC Review Y’all will be super STAARS!

2. Contrasting Prokaryotic and Eukaryotic Cells • Prokaryotic cells contain no nuclear membrane, as well as no membrane bound organelles • Eukaryotic cells do! • How do you remember this? Pro=no nucleus, eu = do (does have a nucleus) The universe conspired to help him achieve it.

3. Comparing Eukaryotic and Prokaryotic Cells • All cells contain- • Cytoplasm • Genetic material • Ribosomes • A cellular envelope/membrane

4. Ribosomes? • What do ribosomes do in a cell? • Ribosomes carry protiens/help assemble protiens • Found on the rough ER

5. The Endoplasmic Reticulum • Cells contain both the smooth and rough ER • The endoplasmic reticulum helps assemble lipid components, protiens, and materials that are going to be exported from a cell • The rough ER contains ribosomes, • How do I remember this? – Rough has Ribosomes (they both begin with the letter R)

6. Lysosomes • What do lysosomes do? • Lysosomes break down lipids, carbohydrates, and protiens • How do I remember that? Lysosomes deal with lipids! (the letter L, along with other biomolecules)

7. The Golgi Apparatus • The Golgi Apparatus is basically the UPS system for a cell • The GA modifies, sorts, and PACKS protiens that will be used in other parts of a cell • Remember—review the organelle sheet in the reference section of y’alls biology binders

8. Homeostasis • Homeostasis means to keep stable internal contidions • Several examples include— • Sweating, shivering, the opening and closing of the stomata in plants

9. Viruses vs Cells • Why are viruses not considered living things? • They CANNOT reproduce without a host. • Viruses are usually composed of a DNA/RNA core surrounded by a protein coat • A capsid is simply the protein coat that surrounds a virus

10. The Lytic Cycle/Bacteriophages • Viruses can reproduce in 2 ways-either through the lytic or the lysogenic cycle • A bacteriophage is a virus that infects bacteria • The lytic cycle occurs when a virus enters a cell, rapidly multiplies, and bursts the host cell • In the lytic cycle, bacteriophages inject DNA into bacterium • After the host cell bursts, it is destroyed and lysed

11. The Lysogenic Cycle • The lysogenic cycle begins in the same manner that the lytic cycle—bacteriophages inject DNA into bacterium • In the lysogenic cycle, the DNA injected integrates its own DNA into the DNA of the host cell • Over time, the virus’ DNA will replicate with the DNA of the host cell • It does not destroy the cell, but bacteriophage DNA can exit the chromosome of the bacteria cell and enters the lytic cycle

12. The Cell Cycle • The cell cycle is composed of 5 sections, • Growth one (and growth 0)—most of the growth occurs in g1 • S/ Dna replication • Growth 2—the shortest section of interphase • Mitosis • Cytokinesis • Ps when not in mitosis/cytokinesis, the cell cycle is called interphase

13. Why do cells divide? • Cells divide for 2 main reasons— • A larger cell places more of a demand on its Dna, and has trouble moving nutritents across the cell membrane • The ratio of surface area to volume does not stay the same as the cell grows • The volume of a cell increases much more rapidly than the surface area

14. Cell Division • The DNA must be replicated (in the S phase), so both daughter cells will have a complete set of DNA • Mitosis occurs, first, then cytokinesis • Mitosis is the division of the nucleus • cytokinesis is basically the division of the cytoplasm and everything else • Unicellular organisms reproduce through asexual reproduction • Multicellular organisms use asexual reproduction to grow in size

15. Chromosomes • A parent cell’s DNA is passed onto the daughter cells in the form of chromosomes • Chromosomes consist of 2 sister chromatids joined at the centromere • One chromatid will go to each daughter cell

16. Mitosis • Mitosis is composed of 4 phases • Prophase, which is the longest • Metaphase • Anaphase • And telophase

17. Prophase • In prophase the chromosomes become visible • The centrioles split and move to opposite ends of the cell • Chromosomes attach to spindle fibers • The nucleolus and nuclear envelope break down • PLEASE NOTE: plant cells do not have spindle fibers

18. Metaphase • Chromosomes line up along the equator of the cell • Yay

19. Anaphase • The centromeres holding the sister chromatids split • The sister chromatids are now considered chromosomes • The new chromosomes group up on polar ends of the cell by the spindles

20. Telophase • The chromosomes become chromatin again • The nuclear membrane re-forms • The spindles break apart • The nucleolus is visible in both clusters of chromatin

21. Cytokinesis---the word I cannot spell • Cytokinesis usually occurs with telophase • Cytokinesis involves a cleavage furrow (for animal cells) or a cell plate (for plant cells)

22. Regulating the Cell Cycle • Cyclins control the cell cycle • Touch is usually a main control factor • These controls can be turned on and off • Cancer is uncontrolled cell growth

23. Biomolecules • There are 4 different biomolecules • Carbohydrates • Protiens • Nucleic acids • And Lipids

24. Macromolecules • Macromoleucles are made of of 1000s of molecules • Formed by polymerization

25. Carbohydrates • Made up of carbon, hydrogen, and oxygen atoms • Main source of energy for living things • Sometimes used for structural purposes • Monosaccharides-such as glucose, galactose, fructose • Polysaccharides-macromolecules formed from multiple monosaccharides

26. Nucleic Acids • Contain hydrogen, oxygen, nitrogen, carbon, and phosphorus • Assembled from nucleotides • Store and transmit hereditary information

27. Proteins • Contain nitrogen, carbon, hydrogen, and oxygen • Composed of amino acids • Enzymes are protiens • Some protiens control reaction rates, regulate cell processes, transport substances, form bones and muscles

28. Lipids • Made mostly from carbon and hydrogen atoms • Not soluble in water • Can be fats, oils, or waxes • Can be used to store energy, biological membranes • Long chains

29. The Chemistry of Life • What are Van der Walls forces? • Van der Walls forces are the slight attractions that develop between oppositely charged regions of near by molecules • Products and reactants— • Reactants react with each other and the energy applied • Products are what are produced, similar to the answer of a multiplication problem

30. Ionic Bonds • Ionic bonds form IONS! • The transfer of electrons from one atom to another • Oppositely charged atoms have a strong attraction

31. Covalent Bonds • Remember- co means between, so covalent is between valent electrons • Covalent electrons travel in both atom’s cloud orbit • A single covalent bond involves 2 electrons • A double involves 4 • A triple involves 6 • Covalent bonds result in MOLECULES!!!!!!!!!

32. Molecules • The smallest unit of most compounds! • yay

33. Solutions and Suspensions • Both are mixtures, and not chemically combined • Solutions are when ions from a compound break off and are attracted to polar molecules, the ions are surrounded by water molecules • Suspensions—instead of dissolving, materials break off into smaller pieces and don’t settle • The movement of water molecules keeps the particles suspended

34. Carbon Compounds • Carbon atoms contain 4 valence electrons, • Very versatile • 4 biomolecules

35. Photosynthesis and cellular respiration They’re located on one of my previous power points………. I’m not going to put it in this one

36. Meiosis and Genes • Genes are located on chromosomes • Homologous-corresponding • We receive 23 chromosomes from each parent that are homologous • Diploid– containing both sets of homologous chromosomes, such as autosomal cells • Haploid—containing only one set of chromosomes—sex cells

37. Because you are probably bored right now…..

38. Meiosis continued • Gametes are haploid • One diploid cell, after meiosis, results in 4 haploid cells

39. Meiosis I/Prophase I • Very similar to mitosis • Prophase one- chromosome pairs with corresponding homologous chromosomes • When homologous chromosomes pair up, it forms a TETRAD! • Crossing over then occurs in PROPHASE ONE • Crossing over results in the exchange of alleles, and allows for diversity

40. Metaphase I • Spindle fibers attach to chromosomes and pull the tetrad apart • The homologous chromosomes are separated :(

41. Anaphase I • In Anaphase I, the homologous chromosomes are pulled toward opposite ends of the cell • Similar to mitosis anaphase

42. Telophase I and Cytokinesis • 2 daughter cells form each with 46 chromosomes, but they don’t have a complete set of chromosomes • Every daughter cell is different • Just like everyone is unique! The end (just kidding, onto round 2)

43. Prophase II/Metaphase II • The second meiotic division, no chromosome replication occurs before this • Metaphase II • Chromosomes line up in the middle or EQUATOR of the cell

44. Anaphase II/Telophase II • The spindles separate the chromosomes into chromatids • Telophase II • Both daughter cells split • Then, the cells are FINALLY HAPLOID! • Yay • Sexual reproduction is both meiosis and mitosis • Asexual reproduction is only mitosis

45. DNA • Transformation—in the Griffith experiment • The dead harmful bacteria transformed the harmless pneumonia bacteria into deadly • The transforming factor might be a gene • Experiments proved that DNA stores and transmits genetic information from one generation to the next • REMEMBER- a group of 3 on a DNA strand is called a triplet

46. Components and Structure of DNA • DNA is composed of nucleotides • Adenine is paired with thymine • Cytosine with guanine • Adenine and guanine are purines, while cytosine and thymine are pyrimidines • Watson and Crick DNA model—DNA is a double helix • Hydrogen bonds allow just enough force to hold the 2 strands together

47. Replication, DNA, and Chromosomes • Chromatin consists of DNA coiled around histones, not in chromosomal form • DNA turns into chromatin which coils into nucleosomes, which turn into coils which turn into super coils which then become chromosomes • DNA’s double helix explains DNA replication—due to base pairing, each strand of DNA can replicate the other • Replication forks are where separation and replication occur

48. Duplicating DNA • Replication must occur before a cell divides • Replication is carried out by a number of enzymes • DNA polymerase unzips DNA molecules and proofreads the new DNA to minimize mutations.

49. RNA and Protein Synthesis • Genes are coded instructions that control the production of proteins within a cell • RNA is a long chain of nucleotides, composed of a 5 carbon sugar (ribose), a phosphate group, and a nitrogenous base • There are 3 main differences between RNA and DNA • 1. The sugar RNA has ribose, DNA has deoxyribose • 2. RNA is usually one stranded • 3. RNA uses uracil, not thymine

50. RNA Continued • RNA can be considered a disposable copy of DNA • RNA is the working copy of a single gene • The assembly of Amino acids is carried out by RNA • 3 Types of RNA • Messenger RNA mRNA • (Ribosomal RNA rRNA, but we didn’t study this) • And Transfer RNA tRNA