2 Organisation of the organism Flashcards
Plant Cells
- Cell wall: Present (made of cellulose)
- Nucleus: Present, close to cell wall
- Cytoplasm: Present
- Chloroplasts: Present
- Vacuoles: Large, containing cell sap
- Cell membrane: Present, surrounded by cell wall
- Shape: Fixed shaped by cell wall
Animal Cells
- Cell wall: Absent
- Nucleus: Present
- Cytoplasm: Present
- Chloroplasts: Absent
- Vacuoles: Small, no cell sap
- Cell membrane: present
- Shape: No fixed shape
Cell Membrane
- forms a barrier between the cell and surrounding
- keep cell contents in
- allow substances to enter and leave the cell (e.g. oxygen, carbon dioxide, and water)
- control movement of other substances into and out of the cell. e.g. glucose
- Partially permeable
Nucleus
- controls all activities in the cell
- controls the development of cell
Cytoplasm
- chemical reactions take place
- contains ribosomes, rough endoplasmic reticulum and vesicles
Chloroplast
-contains chlorophyll needed for photosynthesis
Cell Wall
- Prevent cells from bursting
- Gives shape to cell
- Allow substances to pass through (fully permeable)
Sap Vacuole
- full of water to maintain shape and firmness of cell
- stores salts and sugars
Rough Endoplasmic Reticulum
- ribosomes present on outer surface
- package and transport proteins made by ribosomes
- small pieces of rough ER form vesicles to transport protein around the cell
Ribosomes
- synthesise protein
Mitochondria
- aerobic respiration occurs
- cells with high rates of metabolism
require large numbers of mitochondria to
provide sufficient energy
Ciliated cells
- beat back and forth to create current to move fluid
- move the mucus that traps dust and pathogens in the trachea and bronchi
- move the egg from the ovary to the uterus in the oviducts
Root hair cells
- long extensions give them a large surface area
- absorb water and ions from the soil
Xylem vessels
- cylindrical and empty
- arranged into column-like pipes
- thickened with bands of cellulose and LIGNIN
- carry water and ions up the stems
- support stem and leaves
-made of dead cellulose cells
Palisade mesophyll cells
- closely packed
- contains numerous chloroplasts that trap light energy
- starch grains found in the cytoplasm
- photosynthesis
Ciliated epithelial cell
Moving mucus in the trachea and the bronchi of the lungs. Ciliated cells also move the ovum and zygote down the fallopian tube
Cilia are hair-like extensions of the cell. They are constantly moving and sweep mucus long
Nerve cells
- thin extensions of the cytoplasm like wires
- conduction of impulses
Red blood cells
- Shaped like flattened discs to provide large surface area to volume ratio (biconcave shape)
- contains haemoglobin that carries oxygen
- transport of oxygen
Sperm and egg cells
- reproduction
- gamates
Tissue
group of cells with similar structures, working together to perform a shared function
Organ
structure made up of a group of tissues, working together to perform specific functions
Organ System
a group of organs with related functions, working together to perform body functions
Magnification Calculations
AIM or MIA
Prokaryotes
Organisms that do not have a proper nucleus enclosing their genetic material.
Cell
The smallest basic unit of living organisms. All living organisms are made of cells.
Organism
Any living biological entity, such as an animal, plant, fungus, or bacterium.
Difference between Animal and plant cells
Feature Animal cells Plant cells
cytoplasm √ √
nucleus √ √
mitochondria √ √
vacuole √
cell wall √
chloroplasts √
Features of bacteria cell
cell wall, enclosing the cell
cell membrane, surrounding the cytoplasm
cytoplasm, a substance filling the cell where metabolic reactions take place
ribosomes, for protein synthesis
circular DNA, containing the genetic material
plasmids, small loops of DNA containing a few genes that can be transferred to other bacteria.
Examples of Organ systems
plant shoot
plant root
digestive system
circulatory system
immune system
respiratory system
excretory system
nervous system
reproductive system
Micrometres
1 mm = 1000 μm
