BIOLOGY SUMMARIES. All living things share biochemical reactions eg. DNA and proteins

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Bathsheba Lynch
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1 BIOLOGY SUMMARIES LECTURE 1-Intrductin t Bilgy Evlutin There are 3 life creating theries- Panspermia-ET rigins/infectin f spres frm anther planet/star Special creatin by divine frces Evlutin-tells us Earth has a lng histry-4.5/6 Billin years ld All living rganisms arse frm earlier frms All rganisms related (share a cmmn ancestr) Evlutin is a 2 step prcess 1-Variability 2-Ordering variability by natural selectin All living things share bichemical reactins eg. DNA and prteins A cell is a clsed dmain where chemical reactins required fr life are carried ut Cells have survived by the presence f a cell membrane as a barrier Cells are selectively permeable regulating inflw and utflw. Cell Thery All rganisms cnsist f cells Chemical reactins take place in cells Cells nly arise frm ther cells All cells cntain heredity infrmatin passed n by the parent The first cells were small and simple (Prkarytes) Genetic material was then aggregated int a nucleus bund by membranes (Eukarytes) Shwn by the Cambrian explsin (fssil recrd) Eukarytes=nuclei Prkarytes=n nuclei

2 Lecture 2-Structure and functin f prkarytic cells Eukarytic and Prkarytic cells 3 super kingdms-eukarytes, Archaea, Bacteria Bacteria/Archaea are Prkarytes Prkarytes were the first inhabitants f Earth Cyanbacteria used phtsynthesis t prduce xygen and glucse As O frmed, it drifted int the atmsphere and created the zne Prkarytes- DNA Ribsmes Pili Plasma Membrane Cell wall Capsule Rtary Mtr Flagellum (1-100) Can prduce a muselage t help them aggregate Bacteria prduce resting spres that lay drmant until cnditins imprve Spntaneus mutatins ccur at high frequencies-bichemical diversity Quickly adapt t envirnments fr survival Flagella-Made f the prtein Flagellum Prkarytes divide:

3 DNA replicates after cmbining with cell plasma separate Creates 2 cell Archaea are mre clsely related t Eukarytes than Bacteria Hw d Archaea differ frm bacteria Mrphlgically, they dn't Over 1/2 archean genes were new t science Genetic transcriptin and translatin are mre similar t Eukarytes than Bacteria Archaean lipids and membranes are unusual Archaean lack a peptidglycan wall Mst Archaea are extremphiles N Archaean pathgens Eukarytes have almst equal numbers f genes frm bth Arch and Bac. Euk arisen frm bth Prkarytes are usually unicellular r filamentus Ubiquitus with a wall f murein peptidglycan Simple cell structure with a cell membrane, messme, circular chrmsme and plasmids and small ribsmes. Flagella can als be present and simple when cmpared t Euk. Flagella cmpsed f Flagellin Reprductin by binary fissin LECTURE 3-Eukarytes 1 Eukarytes are cmplex in structure and functin Bichemical reactins islated frm ne anther Can be unicellular r multicellular

4 Eukarytic cells cntain: Nuclei Mitchndria Chlrplasts (in plants) an endmembrane system a cytskeletn (micrtubules and actin) Flagella, linear chrmsmes with histnes large ribsmes ther features The 1 Eukarytic kingdm cntains 4 Kingdms Prtists Fungi Animals Plants Nucleus is the aggregatin f DNA and the cntrl centre f the cell It is surrunded by a duble membrane that is part f the endmembrane system Mitchndria are the pwerplant f the cell they cntain enzyme systems fr the breakdwn f fd mlecules t release energy each is surrunded by a duble membrane inner flds inwards t prduce cristae Chlrplasts-present in kingdms "plants" and "prtista" Catch light energy and synthesise fd mlecules by phtsynthesis base f fd chains cntain green pigment that traps light energy-chlrphyll surrunded by a duble membrane envelpe

5 inner membrane has cmplex flds that frm enclsed sacks f membrane called thylakids that cnnect 2 granae matrix surrunding membrane cmpnents called strma chlrplast pigmentatin varies Green algae-chlrphyll B-mre access t wavelengths f light Brwn algae-chlrphyll C and fucxanthin red algae-phycerythrin and phyccyanin Mitchndria derived frm symbitic, aerbic, purple bacteria Chlrplasts- symbitic, phtsynthetic cells bacteria-cyanbacteria Endsymbisis primary-eukaryte with mitchndria engulfs cyanbacteria secndary-secnd Eukaryte engulfs Eukaryte nuclear pres allw cmmunicatin between nucleus and cytplasm duble membrane rganelles (Mit + Chlr) prbably prkarytes living in eukarytic cell Evidence fr endsymbitic nature f Mit and Chlr mrphlgically similar t Bac surrunded by uter membrane similar t cell membrane invaginates t frm lamellae r cristae Semiautnmus, retaining their wn genme metablism is like prk sme chlr still have bacteria peptidglycan wall between inner/uter membrane cyanphra Lecture 4-Eukarytes 2

6 Divisin f labur in the cytplasm Mitchndria and chlrplasts are fully integrated int the cytplasm yet carry ut specific functins. These rganelles are believed t be derived frm ancient endsymbints There are ther membrane-bund rganelles that carry ut specific functins, these are said t be a part f the endmembrane system Endmembrane system A system f cmpartments that includes all f the membrane-bund cmpnents f the cell exept mitchndria and chlrplasts, including the nuclear envelpe Prvides a surface fr bichemical reactins Cmpnents f the cytplasm are part f a cntinuum and physically jined Cells and cellular cmpnents are dynamic (cntinually changing) Heart f system is Endplasmic Reticulum Als includes: Glgi apparatus Vacules Lyssmes Other membrane-bund vesicle micrbdies Endplasmic Reticulum Heart f the endmembrane system Cnsists f membrane cisternae that ramify thrugh the cytplasm and frm internal cmpartments and channels If ribsmes are attached t the ER = ROUGH ER " " absent = SMOOTH ER Glgi apparatus Cnsists f flattened stacks f membranes/cisternae called glgi stacks Functin in the cllectin, packaging and distributin f mlecules synthesised in the cell

A 2 step process: descent with modification - Variability (via mutations). - Ordering that variability by natural selection.

A 2 step process: descent with modification - Variability (via mutations). - Ordering that variability by natural selection. LECTURE 1: T see bilgy in an evlutinary cntext and review the three generalisatins f bilgy. T understand hw far back we have extended the fssil recrd since the days f Darwin. FIRST GENERALISATION OF BIOLOGY