Plant Cell

Robert Hooke studied the cork under a microscope, where he named it as “cells” after he noticed how they resembled the cells that monks used to reside in

How did the cell came to be?

Cell wall

Rigid structure that supports the cell

Cellulose, pectin, hemicellulose, and glycoproteins

The cell wall is made up of what?

Cytoplasm

A gel-like mixture that fills the cell, excluding the nucleus it is surrounded by the cell membrane

Nucleus

This contains the genetic information of the cell

Increases contrast

Why is staining important?

Increases resolution

Why is adding oil in OIO important?

Nucleolus

Creates rRNA to make ribosome and sends mRNA to the ribosome for protein synthesis

Structural proteins

What helps maintain the cell wall’s structure and shape?

Plasmodesmata

Threads of cytoplasm that passes through cell walls of adjacent cells; enables communication between adjacent cells

Middle Lamella

What glues cells together and is made of calcium and magnesium pectates?

Phospholipid bilayer that has a fluid mosaic model

Describe the structure of the cell membrane

Cell walls

What prevents the cell from bursting due to pressure?

Selective permeability/semi-permeable

Describe the permeability of the plasma membrane

• Transport of molecules

• Maintains cell homeostasis

• Sends and receives signals to/from other cells

Functions of the plasma membrane

Plastids

This organelle:

• Contain photosynthetic pigments

• Responsible for the production of food within plant cells (photosynthesis), storage of products like starch, and synthesis of many classes of molecules

• Needed as cellular building blocks and/or for the function of the plant

Chloroplast

Kind of plastid that has the main function of photosynthesis.

Chlorophyll

Green color of chloroplasts come from?

Gases (such as O2 and CO2), hydrophobic molecules (such as benzene), and small polar but uncharged molecules (such as H2O and ethanol)

What kind of molecules does the plasma membrane allow to pass through?

300 chloroplasts

How many chloroplasts can plant cells hold?

Cyclosis

Circular movement of organelles around the vacuole which can be counter or clockwise; enables better exchange of materials around the cell

Chromoplasts

This organelle:

• Oblong-like bodies that hold carotenoid pigments that exude a bright yellow, orange, or red color

• Responsible for signaling other organisms in the environment when it’s ripe or ready to pollinate

Chromoplasts

Identify the organelle

Leukoplasts

These do not contain photosynthetic pigments and is often found in plants or parts of plants that require storage for materials

Vacuoles

Organelles that store water, pigment, salt, ions, and nutrients that maintain homeostasis

Tonoplast — largest fluid-filled organelle; facilitate uphill transport of many ions and other materials, making their concentration higher in vacuole than cytoplasm

Vacuoles are surrounded by what membrane? What is its function?

Crystals

These are materials that are made of calcium oxalate or calcium carbonate found in the vacuoles of crystal idioblasts

Crystal Idioblasts

Crystals are materials that are made of calcium oxalate or calcium carbonate found in the vacuoles of what specialized cells?

Protecting plants from herbivores, calcium regulation, and metal detoxification

Function of crystals

Vacuole

What organelle is the pink line pointing at?

Druse in Portulaca and Begonia

• star-like in shape, mechanical irritants in toxic plants that regulate calcium and protect against herbivores

Give the crystal name and its description

Prismatic in Tradescantia

• diamond in shape; protects against herbivores

  • caterpillars exhibit feeding aversion for plants with these crystals

Give the crystal name and its description

Cystolith in Ficus

• Grape cluster; occurs at a peg grown from the lithocyst wall

• calcium regulation

Give the crystal name and its description

Raphide in Sanseviera

• needle-like; defenses against herbivores that leave tears in their throat or esophagus

Give the crystal name and its description

Rosette

• star-like; functions in protection against herbivores

Give the crystal name and its description

Plasmodesmata

Identify the organelle

Parenchyma cell/tissue

Collenchyma cell/tissue

Sclerenchyma cell/tissue

What are the types of fundamental plant tissue types?

Dermal

Ground

Vascular

General plant tissue types based on location and function:

Parenchyma cells

Type of simple permanent tissue that can divide at maturity and help regenerate and heal wounds

Parenchyma cells

Identify the cell type

Storage parenchyma

store various substances like water, starch, proteins, etc and act as a food and water reservoir

contains lots of amyloplasts

Storage parenchyma

Identify the cell type

Parenchyma cells

What kind of fundamental cells are these?

Collenchyma cells

What kind of fundamental cells are these?

Provide support to delicate parts of the plants so growth will not be impaired

Primary purpose of collenchyma cells

False

T/F: Collenchyma cells have large vacuoles

Prismatic

Collenchyma cells have tissues comprised of _________ cells that are elongated and shaped spherically

leaves and stems

Collenchyma cells are found mostly in _________

Angular collenchyma

Most common type of collenchyma. In this type of collenchyma cells, thickening of walls occurs only at the corners. Intercellular spaces are absent and they have a circular lumen

False

T/F: Collenchyma cells are present in plants with one cotyledon in their seed

Lacunar, Angular, Annular, Lamellar

What are the specific types of collenchyma cells?

Lacunar collenchyma

This type of collenchyma has intercellular spaces. In this type of collenchymatous cells, thickening is more at the places adjacent to intercellular spaces

Lamellar collenchyma

They are also called plate collenchyma. They have thickened tangential walls and are arranged into ordered rows

Annular collenchyma

The cell walls are uniformly thickened for this type of collenchyma

Sclerenchyma cells

Described as dead cells with a thick lining wall when they mature angular outline and compactly arranged

Roots and mature stems

Sclerenchyma cells are usually found where?

• Helps reduce wilting and provide mechanical support to the plant when elongation has ceased

• Function for protection, water transport and support

Function of sclerenchyma cells

Sclerenchyma cells

What type of fundamental cells are these?

Provide an unmodified image of the cells that help us view the natural and general appearance of a cell before staining

Benefits of using fresh mounts

Epidermis; parenchyma tissue

Where are dermal plant tissues found?

Cortex and pith; parenchyma, collenchyma, and/or sclerenchyma tissue

Where are ground plant tissues found?

Xylem and phloem; parenchyma and sclerenchyma tissues

Where are vascular plant tissues found?

Collenchyma; Parenchyma

Identify the types of fundamental cells (a) and (b) in the Dieffenbachia stem

Sclerenchyma cell

Identify the type of fundamental cell in the Dieffenbachia stem

Scleroids

short cells that are variable in shape and are common in shells of nuts, stones of fruits such as cherries and peaches.

Fibers

long, tapered cells that often occur in groups/clumps in woodm inner bark, and leaf ribs

B is a fiber while A is a sclereid

Identify which is a fiber and which is a sclereid

Parenchyma; Xylem

Identify A and B

aerenchyma cells

Type of parenchyma cells that contain very large intercellular (air) spaces that present in aquatic plants

aerenchyma cells

Identify the type of cell

stellate parenchyma cells

This type of cell is:

• Type of aerenchymatous tissue that helps with the internal circulation of air in plants

• highly branched parenchyma cells connected to each other by means of the branches

Onion (Allium cepa) skin cells

Identify the specimen

Bangka-bangkaan (Rhoeo discolor or Tradescantia) lower epidermis cells

Identify the specimen

Unstained onion (Allium cepa) skin cells

Identify the specimen

Waterthyme (Hydrilla verticillata)

Identify the specimen

Stained tomato (Solanum lycopersicum), contains chromoplast

Identify the specimen

Stained potato (Solanum tuberosum), contains leucoplast

Identify the specimen

Bangka-bangkaan (Rhoeo discolor or Tradescantia) lower epidermis cells

Identify the specimen

Chromoplasts

Leucoplasts

Chloroplasts

What are the types of plastids?

• maintaining cell acidity and turgor pressure

• regulating the storage and transport of substances

• controlling the transport and localization of key

• proteins through the endocytic and lysosomal-vacuolar transport pathways

• responding to biotic and abiotic stresses.

Functions of vacuole

Leucoplast

colorless, storage of starch (e.g.amyloplast)

central vacuole

store a lot of water and swell up so that plant cells can maintain the high turgidity needed for the plant to function optimally

plant crystals

This are:

• final products of plant's cellular metabolic processes

• usually deposited in vacuoles and cytoplasm.

• comes in various shapes

• proposed as a "defense mechanism against herbivore animals, because when these animals chew on these plants, the crystals produce small injuries in the mucosa inducing severe irritation."

Styloids in Tradescaantia elongated, pillar-shaped crystals that are thicker than raphides

Give the crystal name and its description

Chlorenchyma

photosynthetic parenchyma

Chlorenchyma

Identify the cell type

True

T/F: The collenchyma’s protoplast is alive at maturity