Lab 5 : The Cell Biology department

Kingdom: Plantae Like all eukaryotic cells, including animal cells, plant cells contain membrane-bounded organelles. Some of these organelles, and other structures, are common to all eukaryotes, while others are found in plant cells but not in animal cells. Among the distinguished features of plant cells are: Plastid cell wall intercellular connection. Central Vacuole

Activity 1 : show onion epidermis cells under the microscope

Onion epidermis cells

Plant Organelles: Plastids : are organelles that occur only in plants. Their most prominent members are the chloroplasts (greenplast) In leaves Other plastids are the colored chromoplasts flower , tomato & carrot and the colorless leucoplast.

Leucoplasts may be further divided into groups based on physiological function: Amyloplasts accumulate starch (starch grains). Elaioplasts accumulate oils. Proteinoplasts accumulate protein. Etioplasts represent immature chloroplasts and are present primarily in etiolated (light-deprived) plants.

Examples of different plastids: a) is a chromoplast; b) is a leucoplast; c) is a chloroplast.

chloroplasts are membrane-bound organelles and the site of photosynthesis and ATP production in the autotrophic plant cells. Like mitochondria, chloroplasts contain their own circular DNA molecules.

Activity 2 : show the chloroplast drop of d.w

Chromoplasts in tomato

Chromoplasts in carrot :

Flower Inside the petals cell central vacuoles may contain pigments give petals its color & chloroplast also give petals its color Cytoplasmic streaming : Focus carefully on a single cell. If you watch the cytoplasm carefully you should see small particles moving in a process called cytoplasmic streaming.

Starch grain in potato

Algae : Among Protista Have chloroplasts photosynthesis Have many form Examples : Chlamydomonas ( cup – shaped chloroplast ) Spirogyra (spiral chloroplasts)

Spirogyra

Chlamydomonas