cheat sheet biology and more essays title s and all, Lecture notes of Biology

Download cheat sheet biology and more essays title s and all and more Lecture notes Biology in PDF only on Docsity! Wey TC a olcere tole in plants Dr. Nihal Gabr 13/1/2022 Part 1 Types of reproduction Methods of pollination Asexual reproduction A. Bacteria have no nucleus ( no MITOSIS) They reproduce by BINARY FISSION DNA replicate , the cell divide into 2 genetically identical daughter cells 8. Potato tuber : Potato has buds ….buds divide by mitosis …grow aerial shoot and under ground shoot ….aerial shoot will show and develop leaves ….leaves carry photosynthesis …..producing glucose ….condensed into sucrose …translocated through phloem to THE TIPS OF THE UNDERGROUND SHOOT …CAUSE THE TO SWELL AND STORE STARCH …..forming a new potato tuber ( cells are genetically identical) ….which will later be cut from the parent plant 16/1/2022 Part 2 Flower parts Types of pollination Multicellular Fungi Spore Food source on which spore falls Grow feeding hyphae Bread Release extra cellular enzymes to break down large food particles ( starch) into small soluble ones Explain how fungi feed Absorb the food substances ( glucose )to be used as a source of energy from respiration Sporangium Aerial hyphae Reproduce asexually It will grow aerial hyphae Carrying sporangium in which the cells will divide by mitosis Produce more spores The sporangium will rupture So spores released to be carried away by air …falling on another food source Explain how the fungi reproduce Mycelium Feeding hyphae Spores 8 ④ Sepals Green , protect the flower when its in the bud Petals Large colored leaves 1. Attract pollinators ( insects ) ……scented , colorful and have nectary guide lines 2.protect the reproductive organs Stamen : Anther : produce pollen grains that contain the male nucleus / gametes Filaments : hold the anther to deliver / release the pollen grains for pollination Carpel Stigma Style Ovary Ovule Male nucleus . Micropyle Stigma : surface that receives the pollen grain ……and produce nutritive substances to help polleg grain develop the pollen tube Style ; hold the stigma Allow the passage of pollen tube to ovary Ovary : contain ovules that contain female nucleus / gamete Micropyle : small opening in the ovule , allowing the male gametes nucleus to enter the ovule for fertilisation . Nectary glands Found at the base of the ovary ….secrete sugary fluid to attract pollinators https://youtu.be/eqsXc_aefKI Bud- ±④¥ Pollination Fertilisation Seed formation Germination Transfer of the pollen grain from anther to the stigma 1 A Types of pollination Self pollination Anther Stigma Occurs in bisexual flower Transfer of pollen grain from anther of a flower to the stigma of the same flower or in same plant Implications 1. No wastage of gametes 2. Doesn’t rely on pollinators 3. Offsprings will be well adapted to conditions near parents. 1. Less variation 2. Off springs will become more homozygous / increase in homozygosity 3. Variation due to mutation ….lower chance to be expressed 4. Less adaptation to new environmental conditions…less selection and evolution …..increase in competition …..reduce gene pool ….decrease survival chance …higher risk of extinction 5. If there is a disease it will be more frequently inherited . Cross pollination Next slide I ,B Cross pollination Occurs in bisexual or unisexual Transfer of the pollen grain from anther of a flower to the stigma of another flower on another plant but of same species . Implications “ 1. Wastage of gametes 2.rely on pollinators 3. Less chance for offsprings to inherit fav characteristic from parents . 1. More variation 2. Offsprings will become more heterozygous / increase in heterozygosity 3. Variation due to mutation..higher chance to be expressed 4. More able to adapt to new environmental conditions …more selection and evolution …decrease in competition …increase in gene pool ..reduce chance of extinction 5. Besides the diseases are less frequently inherited . Disadvantages Advantages Pollination Fertilisation Male-gamete Pollengrain. Stigma _ Style Ovary. Micropyle. 1. Pollen grain fall / stick on to the stigma..stigma produce nutritive substances to allow germination / development of the pollen tube . 2. Pollen tube grow down through the style …where the pollen tube release extracellular enzymes which digest its way through the style . 3. Male nucleus travel down the pollen tube and enter the ovule through micropyle … where the male and female nuclei will fuse together and form zygote . Seed formation Female nucleus. Micropyle. 'l Cytoplasm with Food storage. Fusion of male and female nuclei Zygote Embryo Divide by mitosis G Plumule. Radical Testa. Walls of ovule ( integument ) 1. Male nucleus enter the ovule through micropyle Male and female nuclei fuse together forming a zygote …… fertilisation 2. Zygote divide by mitosis forming the embryo 3. Embryo develop into plumule and radical 4. Cytoplasm with food storage form cotyledon 5. Walls of ovules form the seed testa Seed formation Cotyledon Cotyledon f ' II ioa :÷ . Seed germination Factors needed for seed germination WOW Warm temperature For enzymatic activity Water Medium for enzymatic activity Oxygen For respiration to release energy for cell division 1. Water enter through micropyle . …in presence of optimum temperature …enzymes will be come activated and they start to break down-the food storage . Starch ………glucose Protein ……..amino acids Amylase Protease 2. More water will enter the seed , so seed teats split , allowing oxygen to diffuse into the seed…used in respiration to release energy. For cell division…and form new molecules Plumule will grow into shoot / stem Radivcal grow inti a root Dormant seed When factors needed for germination-not available . Get two groups of seeds , each of at least 110 seeds Independent : place one group in the light and the other group in the dark Constant/ controlled variables : all seeds should be of same species/ mass / size Kept under same temperature using thermostatic seedling mat Add same volume of water for each group of seeds over 20 days Same concentration of minerals in soil , and same pH Seedlings Dependent : Measure the initial mass, and take 10 seedlings every 2 days and put in hot place or hot oven to allow water to evaporate and record mass every 2 days over the 20 days Repeat Using more seeds to take average and reduce error and exclude anomalies Dependent . independent variable . p l l l l l l l f f ' l l , l l l l l l l ' l l ll ← $0 light Digital balance Measure initial mass Light Dark Check list 1. Parts of flower label and state the function 2. Definition of pollination 3. Types of pollination Self vs cross pollination 4. Methods of pollination 5. Fertilization .....steps 6. Seed formation .....steps 7. Seed gemination .....conditions (TWO) + steps 1.. Little variation 2. Offsprings become homozygous over time / increase in homozygosity 3. Variation due to mutation, with less chance for mutation to be expressed 4. Offsprings will be well adapted to conditions near parents 5. Any change in environmental conditions ,,,they won;t be able to adapt to these changes in the environment so less chance of selection and evolution ......thus increasing chance of extinction. a)-Definition b) . Adu . UsDisadu.my T -Imp . or Implication . Explain long term effect of self pollination on evolution} ✓ . Err → wind and insect (compare shaped flower and pollen grains) . I Ef