LO 1.1 - Cells, Tissues, Ground

Plant Cells

A Nucleus is a membrane-bound organelle found in eukaryotic cells. * The DNA is similar in every cell, but depending on the specific cell type, some genes may be turned on or off. * The nucleus is covered by a nuclear membrane with thousands of pours in it for communication with cytoplasm. * These nuclear pores are only visible with a microscope.

Where cell division takes place. * Directs the growth, development and activities of the cell. * Makes faithful replicas of the DNA for new cells. * Instructs the formation of enzymes and hormones. Cell Organelles and Function

• The cytosol is the “soup” within which all the other cell organelles reside and where most of the cellular metabolism occurs. • Though mostly water, the cytosol has proteins that control cell metabolism and growth.

• Suspends the organelles • Fills the cell and gives it shape • Allows nutrients to move about the cell Cell Organelles and Function

This is a collective term for the cytosol plus the organelles suspended within the cytosol. Plant Cells

Cell Membrane * A thin skin of protein and lipid forming a boundary between the cell contents and the outside. * The membrane is not solid and is self sealing if broken open (it is a fluid moving barrier). * You could look on a cell membrane as a bag which hold the cell together. Cell Organelles and Function

Cell Membrane function * Allows for a** flow of gases**. * Allows water to pass by a process called osmosis. * Allows light to pass through. * Defending the cell against attack. Cell Organelles and Function

• The plant cell wall lies outside the membrane. • It is composed of tiny microfibril of cellulose and other polysaccharides. • It is permeable (no control over the entry and exit of material) Cell Organelles and Function

• It contributes strength, protection and shape to the cell. • Fluid collects in the plant cell vacuole and pushes out against the cell wall. This turgor pressure is responsible for the crispness of fresh vegetables. Cell Organelles and Function

Vacuole * Plant cells have permanent vacuoles. * These are fluid - filled spaces bounded by a membrane. Cell Organelles and Function

Vacuole Function * It is for storing nutrients and waste products, helping to increase the cell size during growth. * Regulates turgor pressure. * Keeps plants upright Cell Organelles and Function

Contain chlorophyll, for photosynthesis. Plastids containing green chlorophyll. * The chlorophyll is responsible for the plant’s green colour * It is where PHOTOSYNTHESIS takes place. It’s how plants breath. Cell Organelles and Function

• This is where cellular Respiration takes place. • They are about the size of bacteria but may have different shapes. • Mitochondria are membrane-bound organelles, and like the nucleus have double membrane. • The outer membrane is fairly smooth. • The inner membrane is highly convoluted, forming folds (cristae). The cristae greatly increase the inner membrane’s surface area. • It is on these cristae that food (sugar) is combined with oxygen to produce ATP - the primary energy source for the cell. Respiration. Cell Organelles and Function

Function of Mitochondria * Mitochondria provide the energy a cell needs to move, divide and grow. * They are the power house of the cell. Respiration. Cell Organelles and Function

Plant Cells

Found in plant cells • Chloroplast • Vacuole • Cell Wall Plant Cells

Plant Cells

Plant Cells

• Chloroplasts • Cell walls • Central vacuole • Plasmodesmata

Plant Cells: Crash Course Biology Video Click for a 10 minute watch Plant Cells

• Meristematic Tissue - newest. • Dermal – epidermis, cuticle protective covering. • Ground – pith or cortex, can have function in photosynthesis, storage, support. • Vascular tissue – conducting, Xylem, phloem. Plant Tissue

• Mother of all tissue (like stem cells in humans) • Group of densley packed cells that have the ability to keep dividing – Meristems give rise to permanent tissues. • Locations: – near tips of roots and stems, called APICAL MERISTEMS. – in side buds and roots. – in vascular bundles (CAMBIUM). – in cork. Like stem cells in humans Plant Tissue

• Apical Meristem • Lateral Meristem • Intercalary Meristem Plant Tissue