Section 1 - The Nature and Variety of Organisms P1 Flashcards
What are the 8 life processes?
Movement
Respiration
Growth Reproduction Excretion Nutrition Sensitive Homeostasis
What is homeostasis?
Control internal conditions like body temperature and blood glucose, so conditions round the cells remain constant.
What is respiration?
Process by which living cells release energy from their food.
What is nutrition?
Obtaining food/nutrients either by eating or making food.
What is movement?
Plants move slowly usually by growing towards light. Animals move faster due to muscle contraction away from predators.
What is excretion?
Removal of waste products.
What is sensitive?
Able to detect changes in the environment and respond accordingly.
What is growth?
Increase in mass/gain more cells and a change in the relative size of body parts.
What is reproduction?
Producing offspring in order for species to survive.
Describe common features of plants:(4)
- have chloroplasts so they can photosynthesise
- cells have cell walls, made of cellulose
- store carbohydrates as starch or sucrose
- multi cellular
Describe common features of animals:(5)
- most have some form of nervous coordination, so they can respond rapidly to changes in their environment
- move around from one place to another
- often store carbohydrate in the form of glycogen
- multi cellular
- cells-no chloroplast, no cell wall
Describe common features of virus:(4)
- have a protein coat around some genetic material
- no cellular structure, particles rather than cells-smaller than bacteria
- only reproduce inside living cells
- they infect all types of living organisms
Describe common features of fungi:(6)
- most feed by saprotrophic nutrition(they secrete extra cellular enzymes into the area outside of their body to dissolve the food, so they can absorb the nutrients)
- cell walls, made of chitin
- store carbohydrates as glycogen
- some are single-celled
- others have a body called mycelium made up of hyphae(hyphae contain lots of nuclei)
- can’t photosynthesise
Describe common features of protoctists:(2)
- single-celled and microscopic
- some have chloroplasts and are similar to plant cells, others are more like animal cells
Describe common features of bacteria:(4)
- most feed off other organisms(both living or dead)
- no nucleus, instead they have a circular chromosome of DNA
- some can photosynthesise
- single-celled and microscopic
What is a pathogen?
A disease causing organism.
What can pathogens be?
{Examples for different living organisms]
Protoctists- plasmodium > malaria
Fungi- yeast > ring worm
Bacteria- pneumococcus > pneumonia
Viruses- HIV > AIDs, influenza virus > flu
What are examples of plants?
Flowering plants:
- maize(cereals)
- herbaceous legumes(peas and beans)
What are examples of animals?
Mammals: -humans Insects -houseflies -mosquitoes
What are examples of fungi?
Yeast (single celled fungus)
Mucor (multi celled, has mycelium and hyphae)
What are examples of protoctists?
Chlorella (plant cell like)
Amoeba (animal cell like, lives in pond water)
What are examples of bacteria?
Lactobacillus bulgaricus (used to make yogurt) Pneumococcus (spherical round shape)
What are examples of viruses?
Influenza virus
Tobacco mosaic virus (tobacco leaves discoloured stopping them from producing chloroplasts)
HIV
Why are viruses not classed as an organism?
Viruses don’t excrete
Viruses don’t grow
Viruses don’t control internal conditions
Out of MR GRENSH only does movement and reproduction
What are the levels of organisation in an organism?
Organelles ➡️ Cells ➡️ Tissues ➡️ Organs ➡️ Organ System
What is a tissue?
A tissue is a group of similar cells that work together to carry out a particular function
What is an organ?
An organ is a group of different tissues that work together to perform a function
What are the two types of cells?
Eukaryotic
Prokaryotic