Variety of Living Organisms Flashcards
What are the main characteristics of living organisms?
- Movement: by the action of muscles in animals, and slow growth movements in plants
- Respire: get energy from their food
- Sensitive (respond to stimuli): they are sensitive to changes in their surroundings and respond to their surroundings
- Nutrition: they require nutrition, by either making their own food, as in plants or eat other organisms as animals do
- Excrete: they get rid of toxic waste products
- Reproduce: produce offspring , in order for their species to survive
- Growth: (and develop) increase in size and mass using materials from their food
- Control their internal conditions, for example temperature and water content
What is an organelle?
Is a structure or part of the cell, organelles have their own membrane
Describe the function of the nucleus
Store DNA and controls the cell
Describe the function of the cell membrane
Controls what enters and leaves the cell
Describe the function of the cytoplasm
A jelly like fluid where all the chemical reactions take place, contains enzymes which control these reactions
Describe the function of the mitochondria
This is where aerobic respiration takes place
Describe the function of the ribosomes
The site of protein synthesis
Describe the function of the cellulose cell wall
Maintains the structure of the cell and protects it (supports and strengthens it)
Describe the function of the chloroplasts
Contains chlorophyll so that they can carry out photosynthesis
Describe the function of the vacuole
Membrane that stores cell sap (sucrose and water), and helps support it
Describe the organisation of an organism, what is each part?
Small to Large:
- Organelles are tiny structures within cells, you can only see them using a powerful microscope
- Cell (cells are specialised to carry out a particular function e.g. RBC and WBC)
- Tissue (a group of similar cells working together e.g. xylem and phloem tissue in plants)
- Organ (several tissues working together e.g. lungs and leaves)
- Organ system (whole organism e.g. digestive system)
What organelles does an animal cell contain?
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
What organelles does a plant cell contain (palisade cell)?
- Nucleus
- Cytoplasm
- Cell Membrane
- Cellulose Cell Wall
- Mitochondria
- Ribosomes
- Vacuole
- Chloroplasts
- Starch grains
What are the five kingdoms?
- Plants
- Animals
- Fungi
- Protoctists
- Bacteria
What is classification?
Is the grouping of living organisms according to similar functions and structures
What is the classification system?
Largest to smallest:
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
What is binomial nomendature?
Two name system:
1. First name is the organisms genus, first letter of genus is always capital
2. Second name is the organisms species, first letter of species is lowercase
Species name is written in italics or underlined
Do plants have chloroplasts? Are plants unicellular? What are their cells walls made of? How do they store carbohydrates? How do they grow?
- Plants are multicellular organisms
- Their cells contain chloroplasts and are able to carry out photosynthesis
- They have cellulose cell walls
- Plants store carbohydrates as sucrose or starch
- They grow in a spreading matter
What are examples of plants?
- Flower
- Mosses
- Grasses
Flowering plants: - Cereals e.g. Maize
- Herbaceous legume e.g. peas and beans
Are animals unicellular? Do they have chloroplasts? How do they store carbohydrates? Do they have cells walls? Do they have nervous coordination?
- Animals are multicellular organisms
- Their cells do not contain chloroplasts and are not able to carry out photosynthesis
- Unable to make their own food so feed on other organisms - heterotrophic
- Compact body shape
- Most are capable of moving around
- Their cells do not have cell walls
- Most have some kind of nervous coordination and are able to move from one place to another and means that they can respond rapidly to changes in their environment
- They often store carbohydrate in the form of glycogen
What are examples of animals?
- Mammals: humans
- Insects: houseflies and mosquitoes
- Fish
Can fungi carry out photosynthesis? How is their body organised? How do they store carbohydrates? How do they feed? How do they reproduce?
- Some are single celled
- Their body is usually organised into a mycelium which is made up from thread-like structures called hyphae. The hyphae contain lots of nuclei
- They cannot photosynthesise
- Their cell walls are made of chitin
- Most feed by saprotrophic nutrition, which is when they feed by extracellular secretion of digestive enzymes onto food material and absorption of the organic products
- They can store carbohydrate as glycogen
- Reproduce by forming spores
What are examples of fungi?
- Yeast: this is a single-celled fungus
- Mucor: this has the typical fungal hyphal structure is multicellular and has a mycelium and hyphae
What are protoctists? What are their cells like?
- These are single-celled (except for large algae) and microscopic
- Some have chloroplasts and are similar to plant cells
- Others are more like animal cells
What are examples of protoctist?
- Chlorella (plant-cell-like), has chloroplasts
- Amoeba (animal-cell-like) and lives in pond water
- A pathogenic example is Plasmodium, responsible for causing malaria
Do Bacteria have a cell wall? Do they have a nucleus? How do they feed?
- These are single-celled and microscopic
- They have a cell wall, cell membrane, cytoplasm and plasmids
- They do not have a nucleus but contain a circular chromosome of DNA
- Some can photosynthesise
- Most bacteria feed off other organisms, both living and dead
What are examples of bacteria?
- Lactobacillus bulgaricus (can be used to make milk go sour and turn into yogurt, it is rod-shaped)
- Pneumococcus (spherical in shape and acts as the pathogen causing pneumonia)
What are viruses? What characteristics can and can’t they carry out?
- These are small particles, smaller than bacteria
- They are parasitic and can only reproduce inside living cells. Organisms that depend on other organisms to live are called parasites
- They infect all types of living organisms
- They have a wide variety of shapes and sizes
- They don’t have a cellular structure, they have a protein coat and contain one type of nucleic acid, either DNA or RNA
- Can’t respire
- Can’t excrete
- Don’t feed
- Don’t move or grow
What are examples of viruses?
- Influenza virus that causes ‘flu’
- Tobacco mosaic virus (this makes the leaves of tobacco plants discoloured by stopping them from producing chloroplasts)
- HIV virus that causes AIDS
What are pathogens? What do they include?
- Organisms that cause disease
- They include some fungi, protoctists, bacteria and viruses
What are some examples of pathogens?
- Protoctist: Plasmodium which causes malaria
- Bacterium: Pneumococcus which causes pneumonia
- Viruses: Influenza viruses (which cause ‘flu’) and HIV (which causes AIDS)
Give examples of different systems
- Nervous/CNS
- Breathing/respiratory/ventilation
- Digestive
- Excretory/urinary
- Skeletal
- Endocrine/hormonal
- Reproductive
- Immune
- Lymphatic
What is an organ?
Tissues that carry out the same function
