Characterists And Variety Of Living Organisms

Question 1

Features of plants (eukaryotic organisms)

Answer 1

• multicellular organisms
• cells contain chloroplasts and are able to carry out photosynthesis
• cells have cellulose cell walls
• they store carbohydrates as starch or sucrose

Question 2

Features of animals (eukaryotic)

Answer 2

• these are multicellular organisms
• their cells do not contain chloroplasts and are not able to carry out photosynthesis
• they have no cell walls
• they usually have nervous co-ordination and are able to move from one place to another
• they often store carbohydrate as glycogen.

Question 3

Features of fungi

Answer 3

• not able to carry out photosynthesis
• body is usually organised into a mycelium made from thread-like structures called hyphae, which contain many nuclei
• others are single-celled
• their cells have walls made of chitin
• saprotrophic nutrition: they feed by extracellular secretion of digestive enzymes onto food material and absorption of the organic products
• they may store carbohydrate as glycogen.

Question 4

Features of protoctists (eukaryotic)

Answer 4

• these are microscopic single-celled organisms.
• some, like Amoeba, that live in pond water, have features like an animal cell
• others, like Chlorella, have chloroplasts and are more like plants
• A pathogenic example is Plasmodium, responsible for causing malaria.
• PROTOZOA LOOK LIKE ANIMAL CELLS
• ALGAE LOOK LIKE PLANT CELLS

Question 5

Features of bacteria (prokaryotic)

Answer 5

• microscopic single-celled organisms; they have a cell wall, cell membrane, cytoplasm and plasmids
• they lack a nucleus but contain a circular chromosome of DNA
• some bacteria can carry out photosynthesis but most feed off other living or dead organisms.

Question 6

What living organisms can pathogens include

Answer 6

Fungi, bacteria, protoctists or viruses

Question 7

Features of viruses

Answer 7

• these are not living organisms
• are small particles, smaller than bacteria
• they are parasitic and can reproduce only inside living cells
• they infect every type of living organism
• They have a wide variety of shapes and sizes
• they have no cellular structure but have a protein coat and contain one type of nucleic acid, either DNA or RNA.

Question 8

What characteristics do all living organisms share?

Answer 8

Movement
Respiration
Sensitivity 
Growth 
Reproduction
Excretion
Nutrition
Homeostasis