Section 1 Structure And Functions In Living Organisms and Cells Flashcards
What are the five stages of organisation? Give an example of each.
Organelles - nucleus, cytoplasm Cells - blood, skin Tissues - xylem tissue Organs - lungs Organ system - digestive
What are the eight characteristics of living organisms?
Movement Respiration Surroundings - react to change Growth Reproduce Excrete their waste Internal control Nutrition
What is an organ?
A group of tissues that work together
What organisms are multicellular?
Plants
Animals
Some fungi
What do viruses contain?
DNA
RNA
Bacteria contain a circular ………..
Chromosome of DNA
What is a pathogen?
Organisms that cause disease
Enzymes are ………… Catalysts
Biological
What molecule is changed in a reaction ?
Substrate
What effect does heat have on enzymes?
Higher temperatures increase rate until the optimum then the enzyme denatures
What is an optimum PH?
The PH they work best at
What is diffusion?
The movement of particles from high to low concentration
What is osmosis?
The movement of water molecules across a partially permeable membrane from high to low water concentration
What is a plant when it takes in water by osmosis?
Turgid
What experiment can be used to investigate diffusion?
Pink agar jelly in dilute acid
How can you investigate osmosis?
Potato cylinders (living)
- cut up potato into cylinders and put in beakers with different sugar solutions (one water and one concentrated sugar solution).
- measure length of cylinders and leave a few cylinders in each beaker for half an hour.
- take cylinders out and measure lengths again.
- if longer, they have drawn in water by osmosis.
Visking tube (non-living)
- tie wire around one end of visking tube and put glass tube in other end.
- pour sugar solution down glass tube into visking tube.
- put visking tube in beaker of water and measure where sugar solution comes up to on glass tube.
- leave tubing overnight, then measure where liquid is in glass tube.
- water should be drawn into visking tube by osmosis which will force liquid up the glass tube.
What is active transport?
The movement of particles from low to high concentration using energy from respiration
What factors affect movement of substances?
Surface area
Temperatures
Concentration gradient
What organelles are in plant cells?
Nucleus Cytoplasm Cell membrane Cell wall Chloroplasts Vacuole.
What organelles are present in animal cells?
Nucleus
Cytoplasm
Cell membrane.
Name the six main groups that organisms are classified into.
Plants Animals Fungi Bacteria Protoctists Viruses.
Give examples of viruses.
HIV, Influenza.
Give examples of Protoctists.
Amoeba, Chlorella.
Give examples of bacteria.
Lactobacillus, Pneumococcus.
