Cells ( transpiration ) Flashcards
Types of cell
Prokaryotic and eukaryotic
Prokaryotic cells
Bacteria
Has a cell wall and cell membrane and cytoplasm
No nucleus ( they are plasmids)
What do Eukaryotic cells contain
Plants - chloroplast ( contain chlorophyll), vacuole , cell membrane
Animal and plants - mitochondria for aerobic respiration, ribosomes for protein synthesis
Equation for magnification
= size of image / size of real object(given in q )
Mitosis process
- cell has to get bigger and make more organelles and the dna replicates
- chromosomes pulled to either end of cell
- cytoplasm divides to create daughter cells which are genetically identical
What is mitosis used in
Asexual reproduction and growth
Meiosis process
- dna replicates like In mitosis
- homologous chromosomes pair up
- divide twice to produce 4 daughter cells ( gametes, eggs/ sperm)
- not genetically identical
- in the daughter cells you get half the number of chromosomes as the original cell
What’s diffusion
Movement of a substance from a high to low concentration
How would you make the rate of diffusion faster ?
Increase Concentration and temp
Larger SA , eg small intestines( villi) , alveoli in lungs
Osmosis
Movement of water from a dilute to concentrated solution across a semi-permeable membrane
Active transport
Particles being moved from low to high concentration
Needs energy to be released via respiration
What’s a stem cell
Undifferented cell of an organism which is capable of giving rise to many more cells of the same types
Where are stem cells found
Embryos
Adult stem cells - bone marrow
Tips of shoots - meristems
Problems and advantages with getting stem cells from embryos
Ethical problems
Can be used in therapeutic cloning- treats paralysis/diabetes- has the same genes as patient
What does a root hair cell do
Its and extension of of the cytoplasm and increase the surface area
