LO 1.1 - Cells, Tissues, Ground Flashcards
Cells: - Structure and function - Cell wall, cell membrane, cytoplasm, nucleus, vacuole, mitochondria, chloroplasts Tissues: - Vascular - Meristematic Ground: - Parenchyma, collenchyma, and sclerenchyma.
Info
Cells
* Every living thing is made from microscopic cells
* Most Eukaryotic organisms have trillions
* That is 12 zeros after the number
* Human body has an average of 37.2 trillion
Plant Cells
Plant Cells
Question
What is the Nucleus?
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.
Question
What is the function of the Nucleus?
Cell Organelles and Function
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
Question
What is the Cytosol?
- 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.
Question
What is the function of the Cytosol?
Cell Organelles and Function
- Suspends the organelles
- Fills the cell and gives it shape
- Allows nutrients to move about the cell
Cell Organelles and Function
Question
What is the Cytoplasm?
Plant Cells
This is a collective term for the cytosol plus the organelles suspended within the cytosol.
Plant Cells
Question
What is the Cell Membrane?
Cell Organelles and Function
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
Question
What is the function of the Cell Membrane?
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
Question
What is the Cell Wall?
Plant Cell only.
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
Question
What is the function of the Cell Wall?
Plant Cell Only
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
Question
What is Vacuole?
Cell Organelles and Function
Vacuole
* Plant cells have permanent vacuoles.
* These are fluid - filled spaces bounded by a membrane.
Cell Organelles and Function
Question
What is the function of Vacuole?
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
Question
What is Chloroplast?
Plant Cells Only
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
Question
What is Mitochondria?
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
Question
What is the function of Mitochondria?
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
Info Graphic
Plant cell under the microscope
Plant Cells
Plant Cells
Question
Plant versus Animal Cells.
What are found only in plant cells?
Plant Cells
Found in plant cells
- Chloroplast
- Vacuole
- Cell Wall
Plant Cells
Info Graphic
Plant Cell
Plant Cells
Plant Cells
Info Graphic
Plant Cells vs Animal Cells.
Plant Cells
Plant Cells
Question
What organelles exist in Plant Cells but not in Animal Cells?
Plant Cells
- Chloroplasts
- Cell walls
- Central vacuole
- Plasmodesmata
Video
Time for a video?
Plant Cells: Crash Course Biology
Click for a 10 minute watch
Plant Cells
Question
What are the main parts of the Plant tissue system?
4 types of tissue
Plant Tissue
- 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
Question
What are the types of Meristematic Tissue?
Three types.
Plant Tissue
- Apical Meristem
- Lateral Meristem
- Intercalary Meristem
Plant Tissue
Question
What is Apical Meristem?
Plant Tissue
Apical Meristem
* Located at roots and Shoot tips. This meristem helps increase the length of the plant.
Plant Tissue
Question
What is Lateral Meristem?
Plant Tissue
Lateral Meristem
* Located in the stem – This meristem helps increase girth.
Plant Tissue
Question
What is Intercalary Meristem?
Plant Tissue
Intercalary Meristem
* Located at the base of the leave or the internodes in monocots only. This meristem helps twigs grow into branches.
Plant Tissue
Info Graphic
Shoot tip in longitudinal section showing the Apical Meristem.
Plant Tissue
Apical Meristem
Plant Tissue
Info Graphic
More Apical Meristems.
This time for Wheat and Barley.
Plant Tissue
Apical Meristem
from Wheat and Barley
Plant Tissue
Info Graphic & Text
Primary growth of a root.
Plant Tissue
Primary growth of a root.
The diagram and light micrograph take us into the tip of an onion root. Mitosis is concentrated in the zone of cell division, where the apical meristem and its products, the three primary meristems, are located. The apical meristem also maintains the root cap by generating new cells that replace those that are sloughed off. If the apical meristem is damaged, its quiescent center is activated and restores the meristem by means of cell division. Most lengthening of the root is concentrated in the zone of elongation. Cells become functionally mature in the zone of maturation. The zones of the root grade into one another without sharp boundaries.
Plant Tissue
Video
Ground Tissue
Time for a video?
2 minutes. Watch till 2:35.
Plant Tissue
Question
What are 3 types of Ground tissue?
Plant Tissue
- Parenchyma cells
- Collenchyma cells
- Sclerenchyma cells
Plant Tissue
Question
What are Parenchyma cells?
5 points.
Plant Tissue
Parenchyma cells
* Oval shaped cells with thin cell walls.
* They also have space between the walls.
* Most widespread - roots, stems, leaves and flowers.
* Relatively unspecialised.
* Formation & storage of food, vascular, healing, regenerating.
Plant Tissue
Question
What are Collenchyma cells?
5 points
Plant Tissue
Collenchyma cells
* They are composed of living elongated cells.
* They provide elasticity, mechanical support.
* Found in stems and leaves.
* Used for flexibility of growing points in the plant e.g. at the tips of climbing stems.
* High in cellulose in some of the corners of their cell walls.
Plant Tissue
Info Graphic
Celery Stalk
Look for Parenchyma and Collenchyma
Plant Tissue
Celery Stalk
Plant Tissue
Question
What are Sclerenchyma cells?
Plant Tissue
Sclerenchyma
* They have extremely thick cell walls containing lignin.
* They protect and support the plant.
* These tissues are present in stems, leaves and in the hard coating of seed and nuts.
Plant Tissue
Info Graphic
Pear - Pyrus communis
Plant Tissue
Pair containing Sclerenchyma cells.
Plant Tissue
Question
What is Epidermal tissue?
Plant Tissue
Epidermal Tissue
* Single layer of regular shaped cells
* Flattened cells pressed tightly together
* Outer walls usually covered with waxy cuticle
Plant Tissue
Question
What is the function of Epidermal tissue?
Plant Tissue
Epidermal tissue function
* Protection
* Prevent excess water loss
* Some specialised as hairs
Plant Tissue
Question
Where is the Epidermal tissue located?
Plant Tissue
Epidermal tissue location
* Surface of root\stem\leaf
* Continuous skin over plant body
Plant Tissue
Question
What is Vascular tissue?
3 points.
Plant Tissue
- Xylem
- Phloem
- Cambium
Plant Tissue
Question
What is Xylem?
3 points.
Plant Tissue
- Xylem
– Tracheids tissue and vessel elements tissue.
– transport water from the roots to the shoot, together with minerals that are dissolved in the water absorbed from the soil.
Plant Tissue
Question
What is Phloem?
3 points.
Plant Tissue
- Phloem
– contains sieve-tube cells, companion cells and parenchyma cells.
– transport organic nutrients, such as glucose for energy or for storage as starch, and amino acids for making proteins.
Plant Tissue
Question
What is Cambium?
3 points.
Plant Tissue
- Cambium
– found between xylem and phloem cells. When activated, they can produce more xylem and phloem (=meristematic)
Plant Tissue
Question
Remember POXI
Plant Tissue
POXI
Phloem on the outsie.
Xylem on the inside in DICOTS.
Plant Tissue
Question
What are Tracheids?
Plant Tissue
Tracheids are elongated cells that transport water and mineral salts through the Xylem of vascular plants.
Plant Tissue
Question
What are Vessel Elements?
Plant Tissue
Vessels (also known as the trachea) are the second type of Xylem element, and they are made up of short, tube-like cells.
Plant Tissue
Question
What are Sieve tube elements?
Plant Tissue
Sieve tube elements, like vessel elements, are connected end to end in vertical rows to form sieve tubes.
Plant Tissue
Question
What is Phloem Tissue?
Hint: Mixed tissue
Plant Tissue
Phloem Tissue
* Phloem Parenchyma
* Phloem Sclerenchyma
* Sieve Tubes
* Companion cells
Plant Tissue
Describe
Describe the Xylem cell type?
6 points
Plant Tissue
Xylem - Carrys Water (from the roots upwards)
* Water conducting (dead).
* Tracheids or vessel elements.
* Tubular, elongate.
* Pits for cell to cell movement.
* Perforated plates at end of cells.
* Aligned end to end.
Plant Tissue
Describe
Describe Phloem sell type.
5 points
Plant Tissue
Phloem - Carrys Sap (in all directions)
* Sieve tube elements (alive).
* Conduct sugars and organic nutrients.
* Little cell contents (no nucleus or vacuole).
* Elongate cell with sieve plate at end.
* Along side cell is a non - conducting cell is called a companion cell and deals with functions for itself and sieve tube.
Plant Tissue
Info Graphic
Recap Tissues
Plant Tissue
Plant Tissue
