Paper 1 Nature and Variety of Life Flashcards
What does MRS NERG stand for
Movement Respiration Sensitivity Nutrition Excretion Respiration Growth also control internal conditions (homeostasis)
Levels of organisation (biggest to smallest)
organ system organ tissue cells organelles
purpose of nucleus
controls cells activities and contains genetic information
purpose of cell membrane
controls what comes in and out of cell
purpose of cytoplasm
gel-like substance where most of the chemical reactions take place
purpose of mitochondria
respiration - produce energy
purpose of ribosomes
protein synthesis
purpose of chloroplasts
photosynthesis
purpose of cell wall
supports and strengthens cell
purpose of vacuole
contains cell sap and helps support the cell and storage
what is a tissue
a group of similar, specialised cells which work together to carry out a particular function
what is an organ
group of different tissues that work together to perform a function
what is an organ system
organs which work together to form an organ system to do a specific job
what does eukaryotic mean
a cell which has a nucleus within the membrane
what does prokaryotic mean
a cell with no membrane bound organelle
which organisms are eukaryotic
animals, plants, fungi, protoctists
which organisms are prokaryotic
bacteria, viruses
how do plants store carbs
as sucrose or starch
how do animals and fungi store carbs
glycogen
features of fungi (6)
some are single celled others have a body called mycelium, made of hyphae, which contain lots of nuclei can't photosynthesise cell walls made of chitin feed by saprotrophic nutrition store carbs as glycogen
what is saprotrophic nutrition
secrete extracellular enzymes out of body to dissolve food so the nutrients can be absorbed
features of protoctists (3)
single celled and microscopic
some have chloroplasts and are similar to plant cells
others are more like animal cells
features of bacteria (5)
single celled and microscopic no nucleus circular chromosomes of DNA some can photosynthesise most bacteria feed off other organisms
features of viruses (5)
smaller than bacteria and are particles rather than cells
can only reproduce inside living cells
infect all types of organisms
come in lots of different shapes and sizes
no cellular structure - protein coat around some genetic material (DNA or RNA)
