1 The nature and variety of living organisms

Question 1

Define eukaryotic cells

Answer 1

a type of cell found in animal, plant, fungi and protoctist cells that contain a nucleus

Question 2

Define prokaryotic cells

Answer 2

a type of cell found in bacteria/ prokaryotes that don’t contain a nucleus

Question 3

What is the acronym that all living things must meet to be classed as living?

Answer 3

MRS H GREN

Question 4

What does M stand for in MRS H GREN?

Answer 4

Movement

Question 5

What does R stand for in MRS H GREN?

Answer 5

Respiration

Question 6

What does S stand for in MRS H GREN?

Answer 6

Sensitivity and ability to respond to changes to environment (stimuli)

Question 7

What does H stand for in MRS H GREN?

Answer 7

Homeostasis

Question 8

What does G stand for in MRS H GREN?

Answer 8

Growth (increasing mass and/ or volume by cellular division)

Question 9

What does R stand for in MRS H GREN?

Answer 9

Reproduction

Question 10

What does E stand for in MRS H GREN?

Answer 10

Excretion

Question 11

What does N stand for in MRS H GREN?

Answer 11

Nutrition

Question 12

What does an animal cell contain

Answer 12

cell membrane, cytoplasm, mitochondria, ribosomes, nucleus

Question 13

What characteristics do/can the organisms in the animal kingdom have?

Answer 13

All multicellular, obtain nutrients by eating other organisms, no chloroplasts, no cell wall, have a nervous system to respond to its environment and stores carbohydrates as glycogen

Question 14

What does a plant cell contain

Answer 14

cell membrane, cell wall, cytoplasm, nucleus, vacuole, mitochondria, ribosomes, chloroplasts

Question 15

What characteristics do/can the organisms in the plant kingdom have?

Answer 15

All multicellular, obtain nutrients by photosynthesizing so also have chloroplasts to do this, have a cell wall made of cellulose and store carbohydrates as starch or sucrose

Question 16

What does a fungi cell contain

Answer 16

body organised into mycelium made from thread-like structures called hyphae, contain many nuclei, cell wall made of chitin

Question 17

What characteristics do/can the organisms in the fungi kingdom have?

Answer 17

Can be multicellular or unicellular (yeast), some have a reproductive structure (mushroom or toadstool), feed by saprotrophic nutrition, cells do not have chloroplasts but do have a cell wall made of chitin and can contain more than one nucleus and store carbohydrates as glycogen

Question 18

what does a bacteria cell contain

Answer 18

nucleiod, plasmids, ribosomes, cell membrane, cell wall, slime capsule, flagellum

Question 19

What characteristics do/can the organisms in the prokaryotic/bacteria kingdom have?

Answer 19

All unicellular and very small, prokaryotic so do not contain membrane bound organelles like a nucleus, genetic material in the cytoplasm as a single circular chromosome, can have a cell wall made of peptidoglycan, can have a slime capsule outside of the cell wall, can have plasmids (circles of DNA containing extra genes), can have a flagellum for movement

Question 20

What characteristics do/can the organisms in the protoctista kingdom have?

Answer 20

All unicellular (made of a single cell), some photosynthesize, others feed on living or organic remains, cells can have chloroplasts, cell walls and a flagella, lots of variation (dustbin kingdom - the kingdom where single celled organisms are put that done meet all of the characteristics of other kingdoms so are placed here)

Question 21

what organisms are multicellular?

Answer 21

Plants, Animals

Question 22

what organisms are single-celled?

Answer 22

Fungi, Protoctists, Bacteria

Question 23

what does a virus contain

Answer 23

It is not a cell as it is not a living organism:
DNA or RNA strand, envelope with attachment proteins, protein coat

Question 24

Why are viruses not classed as being living?

Answer 24

Do not meet any requirements of MRS H GREN/ do not respire.
Not cells or made up of cells and cannot reproduce themselves

Question 25

How do viruses replicate?

Answer 25

Enter host cell, take over the cell by making cells enzymes and ribosomes to make new viruses and then the cell dies, allowing the viruses that have been made by the cells to infect other cells

Question 26

examples of a virus

Answer 26

~HIV - causes AIDS
~Covid 19
~Ebola
~Influezna - causes flu
~Tobacco mosaic virus - makes leaves of tobacco plants discoloured by preventing formation of chloroplasts
~HPV

Question 27

examples of bacteria

Answer 27

~lactobacillus bulgaricus - rod shaped bacterium used in production of yoghurt from milk
~Pneumococcus - spherical bacterium that acts as the pathogen causing pneumonia

Question 28

examples of protoctists

Answer 28

~chlorella - has chloroplasts (features like plant cell)
~amoeba - lives in pond water (features like animal cell)
~plasmodium - causes malaria

Question 29

examples of fungi

Answer 29

~yeast - unicellular
~mucor - typical hyphae structure

Question 30

examples of animals

Answer 30

~Mammals - humans
~insects - houseflies, mosquitos

Question 31

What is a leguminous plant?

Answer 31

Contain mutualistic nitrogen fixing bacteria in nodules on their roots e.g. beans and peas

Question 32

Example of a flowering plant

Answer 32

cereal e.g. maize

Question 33

What is a mosquito?

Answer 33

animal (insect) that acts as a vector that carries plasmodium (protoctist) that causes malaria

Question 34

what is a pathogen

Answer 34

a microorganism that causes disease/ harm to host. All viruses are pathogens

Question 35

what are some examples of pathogens?

Answer 35

Protoctist: Plasmodium causes malaria
Bacterium: Pneumococcus cause pneumonia
Viruses: Influenza virus causes flu and HIV

Question 36

what is saprotrophic nutrition?

Answer 36

extracellular nutrition in which digestive enzymes are secreted onto food outside of cell to break large complex molecules down into smaller more soluble molecules and products of digestion are absorbed by decomposer e.g. proteins into amino acids