Cell Structures, Functions and Transport

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Animal Cell Nucleus Nucleolus Cell Membrane Cytoplasm

Eukaryotic Cell Organelles and Function 1. Nucleus Nickname: “The Control Center” Function: holds the DNA Parts: 1. Nucleolus: dark spot in the middle of the nucleus that helps make ribosomes

Cell or plasma membrane

cell membrane The cell membrane (also known as the plasma membrane or cytoplasmic membrane) is a biological membrane that separates the interior of all cells from the outside environment The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells.

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Animal Cell Nucleus Nucleolus Ribosomes Cell Membrane Cytoplasm

Eukaryotic Cell Organelles and Function 2. Ribosomes Function: makes proteins Found in all cells, prokaryotic and eukaryotic

Eukaryotic Cell Organelles and Function 3. Endoplasmic Reticulum (ER) Nickname: “Roads” Function: The internal delivery system of the cell

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Animal Cell Nucleus Nucleolus Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Cell Membrane Cytoplasm Ribosomes

Endoplasmic Reticulum 2 Types: 1. Rough ER: Rough appearance because it has ribosomes Function: helps make proteins, that’s why it has ribosomes 2. Smooth ER: NO ribosomes Function: makes fats or lipids

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Animal Cell Nucleus Nucleolus Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Ribosomes Golgi Complex Cell Membrane Cytoplasm

Eukaryotic Cell Organelles and Function 4. Golgi Complex Nickname: The shippers Function: packages, modifies, and transports materials to different location inside/outside of the cell Appearance: stack of pancakes

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Animal Cell Nucleus Nucleolus Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Ribosomes Golgi Bodies Cell Membrane Cytoplasm

Eukaryotic Cell Organelles and Function 5. Lysosomes: circular, but bigger than ribosomes) Nickname: “Clean-up Crews” Function: to break down food into particles the rest of the cell can use and to destroy old cells

Section 7-2 Figure 7-5 Plant and Animal Cells Animal Cell Nucleus Nucleolus Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Ribosomes Golgi Bodies Mitochondria Cell Membrane Cytoplasm

Eukaryotic Cell Organelles and Function 6. Mitochondria Nickname: “The Powerhouse” Function: Energy formation Breaks down food to make ATP ATP: is the major fuel for all cell activities that require energy

Animal Cell Nucleus Nucleolus Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Ribosomes Golgi Bodies Mitochondria Cell Membrane Cytoplasm

Now let’s talk about structures only found in PLANT Cells!!

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Plant Cell Cell Membrane Vacuole

Eukaryotic Cell Organelles and Function 7. Vacuoles Function: stores water This is what makes lettuce crisp When there is no water, the plant wilts

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Plant Cell Cell Membrane Vacuole Chloroplasts

Eukaryotic Cell Organelles and Function 8. Chloroplasts Function: traps energy from the sun to produce food for the plant cell Green in color because of chlorophyll, which is a green pigment

Chloroplasts

Section 7-2 Figure 7-5 Plant and Animal Cells Go to Section: Plant Cell Cell Membrane Vacuole Chloroplasts Cell Wall

Eukaryotic Cell Organelles and Function 9. Cell Wall Function: provides support and protection to the cell membrane Found outside the cell membrane in plant cells

Plant Cell Cell Membrane Vacuole Chloroplasts Cell Wall Nucleolus Nucleus Rough ER Smooth ER Golgi Bodies Mitochondria Ribosomes Cytoplasm

Plasmodesmata (singular: plasmodesma) Plasmodesmata are microscopic channels which traverse the cell walls of plant cells and some algal cells, enabling transport and communication between them.

Symplast and Apoplast The symplast of a plant is the inner side of the plasma membrane in which water (and low-molecular-weight solutes) can freely diffuse. the apoplast is the free diffusional space outside the plasma membrane.

The symplast of a plant is the inner side of the plasma membrane in which water (and low-molecular-weight solutes) can freely diffuse.plantplasma membranesolutesdiffuse

Cell types Parenchyma Collenchyma Sclerenchyma

parenchyma Storage Support for photosynthesis Phloem loading Leaves mostly parenchyma cells Thin, permeable cell walls Enable transport of small molecules

collenchyma Have only a primary cell wall Lacks lignin Contain pectin and cellulose Provides plastic support Strings in celery Elongated cells that can be “stretched”

Sclerenchyma 2 types – sclerids and fibres Cells develop a secondary cell wall inside primary cell wall Impregnated with lignin Hard cell wall impregnable to water Sclerids – form hard or gritty structures Fibres – support and tensile strength

Tissue types Xylem Phloem Meristematic

xylem Tracheids and vessel elements Vessels connected together into long tubes Parenchyma and fibre cells Primary (active) and secondary (lignified)

phloem conducting cells, generally called sieve elements Parenchyma cells Companion cells Albuminous cells Fibre/supportive cells

Sieve elements Cell formations that transport sugars through the plant Vacuole and other organelles dissolve Little to impeded movement of fluids Pores at ends of cells called sieve areas

Companion cells Type of parenchyma cells Allow for movement of solutes (water and sugars) from cell to cell Movement is through active “pumping” Cell wall transfer (apoplastic) Plasmodesmata transfer (symplastic)

Sap movement Pressure Flow Hypothesis Polymer trap mechanism

Fungus in phloem

Thousand cankers disease

Red turpentine beetle

Blue stain fungi in pines