Variety and Characteristics of Living Organisms Flashcards
What are the characteristics all living organisms share?
- Movement
- Respiration
- Sensitivity (To surroundings)
- Control
- Growth
- Reproduction
- Excretion
- Nutrition
Which kingdoms are eukaryotic?
- Plants
- Animals
- Fungi
- Protoctists
What are the key features of a eukaryotic organism?
- Multicellular or unicellular
- A nucleus
- A distinct cell membrane
They do share specific cell strucures as covered in the next deck
Are plants multicellular or unicellular?
Multicellular
What is the organelle that plants contain which is necessary for photosynthesis?
Chloroplasts
How do plants create their food?
Photosynthesis
Plants are autotrophs
What are plant cell walls made out of?
Cellulose
What do plants store carbohydrates as?
Starch
What are some examples of plants?
- Flowering plants such as cereals (e.g. maize)
- Herbaceous legumes (also flowering) such as peas or beans
Are animals multicellular or unicellular?
Multicellular
Do animal cells contain chloroplasts?
No
As they do not photosynthesise
Do animal cells contain cell walls?
No
How do you describe animals ability to move?
Nervous co-ordination and the ability to move from place to place
What do animals store carbohydrates as?
Glycogen
Can fungi photosynthesise?
No, they use saprotrophic nutrition
Are fungi unicellular and/or multicellular?
- Both
- Unicellular fungi include yeast
- Multicellular fungi include mushrooms and mucor
How are fungi’s bodies organised?
- Into thread like structures called hyphae - the cells of which contian many nuclei
- The many hyphae are collectively referred to as mycelium
This obviously only applies to multicellular fungi
What are fungi cell walls made out of?
Chitin
How do fungi obtain nutrients?
- Saprotrophically
- They secrete extracellular digestive enzymes onto food material and and absorb the digested molecules
- They mostly feed off decaying matter, although parasitic fungi feed off of living matter
How do fungi store their carbohydrates?
They store them as glycogen
Are protoctists unicellular or multicellular?
Unicellular
Protoctists are microscopic
How does nutrition work for protoctists?
- Some photosynthesise
- Some feed off organic living matter or dead matter (heterotrophy and saprotrophy)
Examples of protoctists
- Chlorella - Is more like a plant cell, has chloroplasts, a cell wall and photosynthesises
- Amoeba - Lives in pond water, has features more like an animal cell
- Plasmodium - Pathogenic and causes malaria
Which kingdom is prokaryotic?
Bacteria
What are the key features of prokaryotic organisms?
- Unicellular
- No nucleus - the genetic material is found in the cytoplasm
- Prokaryotic cells are much smaller than eukaryotic cells
Are bacteria multicelluar or unicellular?
Unicellular
(Bacteria are microscopic)
Do bacteria have cell walls?
Yes - made of peptidoglycan
How do bacteria store their DNA?
- A circular chromosone of DNA in the cytoplasm called the nucleoid
- Plasmids - Small circular loops of DNA that contain genes (independent of the chromosomal DNA) found in the cytoplasm as well
How does nutrition work for bacteria?
- Most feed off other living or dead organisms (heterotrophs and saprotrophs)
- Some have chlorophyll (though not chloroplasts) and photosynthesise
Examples of bacteria?
- Lactobacillus bulgaricus - Used in the production of yoghurt
- Pneumoccus - A pathogen which causes pneunomia
What is the definiton of a pathogen?
Any microorganism that causes disease in another organism
Which kinds of microorganisms can be pathogens?
- Bacteria
- Viruses
- Fungi
- Protoctists
Are viruses alive?
No, as they do not fit into MRS GREN
How big are viruses?
Extremely small, smaller than bacteria
What do viruses need to reproduce?
They must be inside the cells of other living organisms
Which organisms can viruses infect?
All types of organisms
What does the structure of a virus look like?
- No cellular structure
- Just a protein coat surrounding some type of nucleic acid (RNA/DNA) acting as their genetic material
Examples of viruses?
- Tobacco mosaic virus - discolours leaves of tobacco plants by preventing formation of chloroplasts
- Influenza - causes the flu
- HIV - causes aids
