Stem cells- plants

Meristem:

Regions of ... cells in plants contain stem cells which rapidly undergo... and ... into specialised cells

Found in root, shoot + cambium

Thin walls, little cellulose and vacuole, no chloroplast

unspecialised, mitosis, differentiate

Cambium cells: layers of actively dividing cells between ... + ...

Secondary growth of stems + roots = ... the plant

Production of xylem, phloem and ... cells

xylem, phloem, thickens, companion

The two vascular tissues are...

xylem and phloem

Xylem:

Transports... in ... direction, lignin kills and ... the cell, breakdown of end walls creates an ... ... column

water, one, hollows, elongated continuous

Phloem:

Transports ..., ..directional, companion cells actively transport ... in and out, lacks organelles + elongated = more space for... transport

sieve plate allows ... of solute

sugars, bi, solutes, solute, movement

Root hair cells:

Absorb ... + ... from soil, large SA:V, lots of mitochondria + special carrier proteins for ... ... of mineral ions

mineral ions entering cell = ?

so water enters via...

minerals, water, active transport, lower water potential, osmosis

Waxy cuticle:

Prevents ... and ...

water loss, pathogen entry

Upper epidermis:

Flattened cells = ... layer, transparent + lack...

protective, chloroplasts

Palisade mesophyll:

Many long + thin chloroplasts for ..., large vacuole pushes chloroplasts to the edge for..

Cytoskeleton threads move chloroplasts for..

photosynthesis, co2 to diffuse into the cell, max light absorption

Guard cells:

Control entry/exit of ... into leaf

Control depends on... of cells

gases, turgidity

Guard cells: (shrunken)

1. Active transport of K+ ions from neighbouring lower ... cells into guard cells

2. Lowers ... ... of cell

3. Water moves ... the guard cell

epidermal, water potential, into

Guard cells: (swollen)

Inner cell wall = thicker so ... to open

1. Water moves ... the guard cell

2. Thinner cell wall bulges outwards, partly moving the ... inner wall with it

3. Gap between guard cells ...

4. Allows entry of co2 + exit of o2 + h2o

rougher, into, thicker, widens