Unit 1 Cell, Tissues done Flashcards
Levels of Organisation, Cells and organelles, Stem cells, Microscopes
Characteristics of living organisms (no need for exam)
Every Elephant in India Never Roams, Munches Grapes, and Rests.
Excretion
Expire
Irritability
Nutrition
Reproduction
Movement
Growth
Respiration
Level of Organisation /
Hierarchy of life
A group of atoms make up molecule. Ex :(H2O)
A group of molecules make up make up organelles. Ex: Mitochondria.
A group of organelles make up cells.
Ex: RBC
A group of cells make up tissues. Ex:nerve tissue
A group of tissues make up organs. Ex:Heart, Kidney.
A group of Organs make up organ systems. Ex: nervous system
A group of organ systems make up organisms. Ex: Humans, Fox
Uni cellular and Multicellular organisms with cell types (Animal and plant cells)
Uni cellular like bacteria are organisms made of only a cell but perform all functions like multicellular organisms.
Multi cellular like animals and plants have more than one cell.
Animal cell: no cell wall, plastids.
Have centrosomes and lysosomes
Nucleus in the centre and many small vacuole.
Plant cell: With cell wall, chloroplast, plastids.
No centrosomes or lysosomes.
Nucleus in one side, large vacuole.
Types of cells, tissues
Cells are the smallest structural and functional unit of life. They are made up of Organelles
Prokaryotic cells (Pro=No): without nucleus, bacteria viruses
Eukaryotic cells (Eu=Do): with nucleus, animals
Cells: Red blood cells, white blood
cells, nerve cells, epithelial cells
Tissues are a group of similar cells that work together to carry a specific function.
Tissues: nervous tissues, epithelial tissues.
Light vs electron microscopes (no need for the exam)
Light: use a light source and 2 lenses,
Can’t see ribosomes, lower magnification, resolution and price than electron microscopes
Can use living samples
Coloured images, 2D only.
Electron microscopes: Use electron beams, can see Ribosomes, Higher magnification, resolution, and price than the light microscopes.
Can’t use living samples.
Only black and white. Can use 3D Figures.
What are stem cell and their types
They are unspecialised cells that are able to develop into different cells.
Tissue specific: Replace cells in organs (only turns to a specific type of cells)
Ex: neural stem cells in the brain can turn only to neural based cells only.
Embryonic stem cells: used only in the early life stages. Can turn into any cell type. Found in the blastula.
Induced embryonic stem cells: Other normal cells that scientists changed to behave like embryonic stem cells.
Endoplasmic Reticulum
A network of double membranes scattered in the cytoplasm that connects the nucleus with cell membrane and provides mechanical support to the cytoplasm.
Rough ER: has ribosomes attached to it’s surface
(function is protein synthesis)
Smooth ER: lacks ribosomes, functions as a transport channel for parts of the cell.
(Lipids synthesis)
Ribosomes
The smallest organelle in size. Responsible for Protein synthesis.
Found attached to Rough Endoplasmic R., free in the cytoplasm or inside Mitochondria and Chloroplasts.
no need in the exam:
Contains RNA and proteins.
Consist of large subunit and small subunit.
2 types 70s in prokaryotes and 80s in eukaryotes.
Golgi apparatus / traffic police
Single Membrane organelle
Named dictyosomes in plant cell
Storage and transportation of protein (traffic police), and secretion of enzymes.
Lysosomes/housekeeper/suicidal bags
Only in animal cells
Single membrane bag like organelles
Present a lot in every cell.
Contains digestive enzymes to destroy and digest any foreign material left like bacteria.
Digest broken or poorly working organelles and can digest the whole cell if it’s diseased or damaged.
Mitochondria / Power house if the cell
*Check Image
Rod shape double membrane organelle visible in the cytoplasm.
Contains its own DNA and ribosomes.
Produce and provide ATP to the cells.
Study the structure
Centrosome
Only in animal cells near the nucleus
2 parts called centrioles
Help in cell division.
Plastids
Check Image: Chloroplast
Small spherical double membrane organelles that have their own DNA and ribosomes in plant cells.
3 Main Types:
Leucoplast:
Colourless, functions in storage found in storage cells of roots and underground stem like potato.
Chromoplast: Yellow to orange red colour. Impact the colour of the petals of flowers and fruits.
Chloroplast: Green in colour due to having chlorophyll. Found in green parts of the plant.
Responsible for photosynthesis.
Can divide on their own.
Vacuoles
Single membrane bound in cytoplasm.
Like a storage bag filled with semi solid liquid.
Few and small in animal cells
1 big vacuole that take 90% of the cell volume.
