Plant Tissues Study Guide

Plant Tissues

• Plant tissues are categorized into meristematic and permanent tissues.
• Meristematic tissues are actively dividing tissues found in specific plant regions.
• Apical meristems are at the tips of stems and roots, increasing length.
• Lateral meristem (cambium) is in the vascular bundles, increasing girth.
• Intercalary meristems are near nodes and help internodes elongate.
• Meristematic cells have dense cytoplasm, thin walls, prominent nuclei, and lack vacuoles.
• Permanent tissues are formed from meristematic tissues after losing their ability to divide.
• Simple permanent tissues include parenchyma, collenchyma, and sclerenchyma.
• Parenchyma has thin walls and large intercellular spaces; stores food and aids photosynthesis.
• Collenchyma has irregularly thickened walls; provides flexibility and support.
• Sclerenchyma has thick, lignified walls, no internal spaces, and provides strength.
• Complex permanent tissues include xylem and phloem.
• Xylem transports water and minerals, including tracheids, vessels, xylem parenchyma, and xylem fibers.
• Phloem transports food, including sieve tubes, sieve cells, companion cells, and phloem fibers.
• Protective tissues include epidermis and cork.
• Epidermis is a single outer layer that secretes a waxy cuticle to prevent water loss.
• Stomata are pores for gaseous exchange and transpiration.
• Cork is formed from secondary meristem and contains dead cells with suberin; provides insulation preventing water loss.

Animal Tissues

• Animal tissues are categorized into epithelial, connective, muscular, and nervous tissues.
• Epithelial tissues cover and protect surfaces, line cavities, and regulate material exchange.
• Epithelial tissue types include simple squamous (thin and flat), stratified squamous (multiple layers), cuboidal (cube-shaped), columnar (tall and pillar-like), ciliated columnar (with cilia), and glandular (secreting substances).
• Connective tissues support, connect, or separate tissues and organs.
• Blood contains a liquid matrix (plasma), transporting gases, nutrients, and waste.
• Bone is a hard matrix made of calcium and phosphorous providing structural support.
• Cartilage is flexible and smoothens joint surfaces.
• Tendons connect muscles to bones, while ligaments connect bones to bones.
• Areolar tissue connects skin to muscles and fills spaces, supporting organs.
• Adipose tissue stores fat and acts as an insulator.
• Muscular tissue is responsible for movement.
• Types of muscular tissue include striated (voluntary, attached to bones), smooth (involuntary, in organs), and cardiac (involuntary, in the heart).
• Nervous tissue transmits signals across the body.
• Nervous tissue is composed of neurons.
• Neurons have cell bodies, dendrites (receiving signals), and axons (transmitting signals.).
• Nervous tissue is located in the brain, spinal cord, and nerves.