Plant Flashcards
What are the levels of organisation
Cell
Tissue
Organ
Organ system
Organism\
What 2 systems do plants consist of
Root system-
Shoot system
Root system
It absorbs water and nutrients from the soil and provides the plant with support and structure
The many branches and the root hair cells increase SA
Shoot system
(all systems besides root system)The shoot system contains the reproductive (flowers and fruits) and non reproductive sections (leaves/stems)
Function of roots:
-Absorb water and nutrients from the soil
-Provides support for the plant
Subcategories of roots:
-reproductive section
-vegetation section(not reproductive)
PATHWAYS OF WATER AND NUTRIENT ABSORPTION IN ROOTS:
Extracellular pathway
Cytoplasmic pathway
Cytoplasmic pathway
mineral ions or small amounts of water either passively diffuse into the cytoplasm or are taken up via active transport in root hair cells.
Extracellular pathway-
water and solute diffuse into the gaps between the cells.
Categories of plants:
Vascular plants eg. scrubs and trees
Non vascular plants eg. moss or liverworts
Vascular plants –
contain vascular tissue which are responsible for transporting water and nutrients throughout the plant.
-There are 2 types of vascular cells
xylem cells and phloem cells
Non vascular plants
do not contain vascular tissue and only require simplified tissue to function-absorb water and nutriejnts directly into theitr cels
What kind of transport occurs non vascular plants
passive tranpsort of water, nutrients and wastes
Why do non vascular plant only require passive transport
Non vascular plants passively transport substances because theyhave a high surface area to volume ratio, and substances simply diffuse across the small distances around the plant
DICOTS
is an example of a vascular plant
a group of flowering plants including fruits
where are vasculra tissue located
vascular bundles
The vascular bundles are made out of
phloem and xylem cells
Plant cells consist of 3 different tissues:
dermal tissue
vascular tissue
ground tissue
Dermal tissue
lines the outside of plants & secretes waxy substances called a cuticle to form:
-Physical barrier between a plant and it’s environment
-To reduce water loss and physical damager
Vascular tissue:
Responsible for transporting water and nutrients around the plant ]
Ground tissue:
makes up the majority of the interior of the plant, through which the vascular tissues extend
Carries out metabolic processes
What makes up vascular tissue:
Xylem cells
Phloem cells
Parenchyma
Sclemythyma
Collmehtyme
Xylem cells
responsible for the transport of water and nutrients from root to the leaves for photosynthesis
what kind of direction are xylem cells
what kind of dirceton are phloem cells
xylem cells are unidrectinal
phloem cells are bidirectional
Phloem cells
responsible for the transport of sugars and other nutrients throughout the plant
Parenchyma
responsible for photosynthesis and some metabolic activites
Sclemythyma and Collmehtyme
provides support for the plant
Vascular plant organs
Leaves
Flowers
Fruits
Stems
Roots
Function of water
Water is a medium for the function and transport of materials around a plant
- it prevents plants for overheating
Why is water important to life?
metabolic reactions like photosynthesis
transporting nutrients and waste around the plant
preventing plants from overheating through evaporation
ensuring cells have the right tonicity
preventing wilting and/or damage from dehydration in the plant.
function of leafs
site of gas exchange and photosytehsnsi
function of fruits
spread the seeds and allow plant to reproduce
stems
supports leafs, stems, flowers and transports water and nutrients between roots and shoots
translocation of sugar
movement of sugar from suagrs from source cells to sink cells through the phloem
explain the pressure flow model of how the phloem works
sugar is produced photosythensis. Then sugar moves into the phloem by acitve transport through membrane transport protein or by simple diffusion. It moves down the phloem to the roots, under pressure caused by osmosis.
why do phloem cells have no nucleus
to make space for the passage of sugar
a vascular tissue in the roots of a dicot plant such as a rose bushare containted in
the stele at the centre of the root
Distinguish between vascular and non vasicular plants 2 marks
Vascular plants are composed of vascular tissue and transport water and minerals whilst non vascular plants are not composed of vascular tissue and only require simplified tissue to function and absorb water and nutrients directly into their cells
differiante between phloem tissue and xylem tissue
phloem tissue are tubes that transport sugars around the plant in both directions
xylem tissue are tubes that transport water and minerals in one direction from the roots to the leaves
How does wind affect transpiration rate?
the wind will blow off any layer of humid air around the surface of the stomata and thus this will increase the amount of water vapour that exits the plant and therefore, the transpiration rate increasses
Using your understanding of concentration gradients explain how air flow and humidity affect the rate of transpiration 4 marks
If the humidity is low and the airflow is high which will blow off the humid layer around the plant’s stomata, this can mean that the concentration of water vapour outside the plant is lower compared to the inside of the plant and thus, more water vapour will evaporate DOWN the concentration gradient increasing the transpiration rate
Using your understanding of concentration gradients explain how air flow and humidity affect the rate of transpiration 4 marks
If the humidity is low and the airflow is high which will blow off the humid layer around the plant’s stomata, this can mean that the concentration of water vapour outside the plant is lower compared to the inside of the plant and thus, more water vapour will evaporate DOWN the concentration gradient increasing the transpiration rate and vice versa
Describe the role of xylem tissue and how it is adapted to carry out it’s function (tip:
The xylem tissue is made out of long hollow tubes which allwos the water to move up the plant. these tubes are made out of vessel elements and tracheids which contain pits that allow the horizontal movement of water within the the xylem.
Also, the cells are lignified which allows them to provide support and strength to the plant
5.Why are the sieve tube cells called so?
sieve tubes contains small pores to allow for water filtration
- To where does the plant translocate food?
from leaves to the rest of the plant
describe how xylem assists in water trasnport in the sunflower of a plant
water moves up the xylem vessels by cohension between water molecules and adhesion between water molecules and the sides of the xylem walls which allows water to move up the xylem via capillaryaction
What is the benefit of cells having a high surface area to volume ratio?
A high surface area to volume ratio increases the rate of diffusion across a cell surface.
What is the benefit of cells having a high surface area to volume ratio?
A high surface area to volume ratio increases the rate of diffusion across a cell surface.
What is the benefit of cells having a high surface area to volume ratio?
A high surface area to volume ratio increases the rate of diffusion across a cell surface.
What is the benefit of cells having a high surface area to volume ratio?
A high surface area to volume ratio increases the rate of diffusion across a cell surface.
