Science Guide to 7th Grade

Chapter 1

Section 1: discovering cells

• Cells are the basic units of structure in a living thing.
• Cells were first discovered by Robert Hooke who used a microscope on cork and found dead cells.
• The transmission is the strongest microscope besides for the tunneling.
• the transmission uses electrons.
• Schleiden said all plants were made of cells.
• Schwann said all animals were made from cells.
• Virchow said all living things are composed from cells.
• virchow said all cells made from other cells.
• ^^^^These statements were gathered and made the cell theory.
• 2 or more

[pic 1]

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ is a diagram of a microscope remember these parts !!

Section 2:Looking in cells

• Animal cells have centrioles and lysosomes

      [pic 2][pic 3][pic 4]

• Plant cells have chloroplast and a bigger vacuole and starch grains and cell wall
• They both have E.R., Mitochondria, Nucleus, Nucleolus, golgi body, Ribosomes, cytoplasm, and Membrane
• Cytoplasm is the filling of the cell
• E.R. transports proteins (hallways)
• Membrane controls what goes in and out it is phospholipid bilayer
• Cell walls  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ more
• bacteria, fungus also have cell walls
• most of the cells we have are specialized
•  Mitochondria power the cell through breaking glucose the have double membrane makes ATP
• Chloroplast capture solar energy (only in plant cells)
• Nucleus has chromatin (DNA) which is basically the blueprint on how to run the cell it has pores (holes) that connect to E.R..
• vacuole = storage tank  basically Vacuole holds stuff
• plant cell has big vacuole
• animal cell has multiple
• lysosomes = garbage dep. Lysosome breaks down stuff using enzymes
• Chromatin can condense to chromosomes that play a role in mitosis and meiosis
• Nucleolus makes ribosomes nucleolus inside nucleus
• Golgi Body package materials and sends them (amazon)
• Lysosome breaks down stuff using enzymes
• centrioles play a big role in cell division
• Ribosomes make proteins
• bars = cell wall / screen = membrane  (brooklyn windows)

                   Section 3:Chemical Compounds in cells

• lipids = fats oils (C,H,o)
• carbohydrates =sugar ( C,H,O)
• proteins = meats chicken made of amino acids (C,H,O,N,S)
• Nucleic acids = DNA + RNA
• amino acids = smaller pieces that come together to make proteins

• know periodic tables in your notes
• carbon = key element for all organic compounds
• hydrogen in all organic compounds  vital for life
• nitrogen critical for proteins  + nucleic acids
• sodium important for water balance in cells and organisms
• Oxygen we need for respiration needed for life
• Potassium Is important for water balance in cells and organisms
• Chlorine Water balance + other stuff
• Sulfur in amino acids and thus some proteins
• Phosphorus part of cell membrane ATP needed for bones

• elements cannot be broken down anymore made by atoms
• compounds made by molecules

    Section 4:The Cell in Its Environment 

•  Diffusion is when the molecules spread due to more in one area then another area
•  Osmosis is when water molecules move from an area of high concentration to an area of lower concentration it does not require energy
•  passive transport does not require energy osmosis and diffusion also does not
•  Active transport is using energy Engulfing uses energy (endocytosis) transport proteins use energy too
• endocytosis = engulfing
• exocytosis looks like an acne commercial

                        Chapter 2:Cell processes and energy

Section 1:Photosynthesis with accel.

• autotroph make food heterotroph kills things and eats them
• pigments are colored chemicals that capture energy
• chloroplast is a pigment
• Carbon dioxide enters the plant through the stomata
• carotenoids xanthophylls and anthocyanins are pigments
• ribosomes are in chloroplasts
• In the chloroplasts the light reactions occur in the thylakoid membranes
• A plant needs CO2 H2O and RAYS FROM SUN
• The calvin cycle is the dark reactions that occur in the stroma
• magnesium is in chlorophyll
• Photosynthesis
• 6CO2+ 6H2O-------->C6H12O6+O6
• from one glucose molecule 30 to 38 atp are produced from resp.

        Section 2: Respiration and accel

• Glycolysis occurs in cytoplasm it breaks down glucose
• Krebs cycle breaks down glucose even more
• It has a folded membrane called the cristae it is where electron transport occurs
• In both photo. and resp. electron transport occurs to slowly release energy
• The krebs cycle occurs in matrix
• Plants use photosynthesis and respiration animals just use resp.
• Fermentation does not use oxygen lactic acid fermentation: happens in the making of beer and bread alcoholic fermentation:happens in us when we run out of oxygen due to hard running
• from one glucose molecule 30 to 38 atp are produced from resp.
• Ethyl alcohol is produced in alcoholic fermentation
• chemosynthesis is used instead of photosynthesis in deep sea vents by unusual bacteria

                                        Section 3: Cell division

• Interphase is when a cell grows and copies its dna to prepare for cell division
• in prophase the cell condenses chromatin to form chromosomes
• in metaphase the chromosomes line up across the center of the cell
• Anaphase is when the centromeres split
• telophase  nuclear envelope forms around the chromosomes
• Cytokinesis is when the membrane pinches each cell ends up with identical DNA

                                Chapter 3:genetics and heredity

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