BIOLOGY Unit 2 Notes: Plants, Animals & The Endosymbiotic Theory

(1) Plant vs Animal Cells Both plants and animals are made of cells. Because they complete different life processes + live in different environments, they require different things. Plants and Animals have unique, individual structures, to help them stay living and healthy. These “structures” are called ORGANELLES.

(2) Only Plant Cells Have… Enlarged Vacuole: Stores extra water for photosynthesis. Helps increase rigidity of plant structure. Chloroplasts: Converts sunlight + CO2 + water into sugars and O2. Cell Wall: Extra barrier around the whole cell.

(3) Only Animal Cells Have… Peroxisomes: Used to break down Hydrogen Peroxide using catalase. Hydrogen Peroxide is a by-product of lipid metabolism in animals.

(4) Both Plants & Animals Have… Cell Membrane Nucleus Endoplasmic Reticulum Golgi Body Lysosomes Ribosomes

(5) The Endosymbiotic Theory States: Modern eukaryotic cells evolved from free-living prokaryotic cells living symbiotically with larger unicellular organisms. Evidence: Mitochondria & Chloroplasts have… DNA Cell Membranes Ability to Reproduce Ability to Produce Proteins