characteristics of living organisms

Question 1

Plants’ characteristics

Answer 1

1) They are multicellular
2) Cells contain chloroplast
3) Carry out photosynthesis and therefore make their own food ( autotrophic (self nutrition)
4) Have cellulose cell walls
5) store carbohydrate as starch ( a group of glucose) or sucrose (2 glucose).
6) Ex. Maize (cereal), Peas & Beans (Legume)
Carbohydrate ( starch. glucose, sucrose, cellulose)
( carbohydrate: carbon dioxide+ water + Hydrogen)

Question 2

Animals’ characteristics

Answer 2

1) They are multicellular
2) Do not contain chloroplast and cannot carry out photosynthesis.
3) Get their nutrition from feeding on other organisms ( heterotrophic)
4) They have no cell wall
5) They have nervous coordination and are capable of movement
6) store carbohydrate as glycogen
6) Ex. mammals (humans), insects ( housefly, Mosquito)

Question 3

Fungi characteristics

Answer 3

1) Cannot carry out photosynthesis
2) cell wall made of CHITIN
3) The body is organized into Mycelium which is made of thread-like structures called HYPHAE which contains many nuclei.
4) Feed by Saprophytic nutrition using Extracellular hydrolytic enzymes.
5) store carbohydrate as glycogen
6) ex. Mucor (multicellular), Yeast ( single-celled fungus)

Question 4

Bacteria characteristics

Answer 4

1) Microscopic single-celled organisms
2) They have a cell wall made out of murein (peptidoglycan), cell membrane, cytoplasm and plasmids (extra loop od DNA), Flagella, DNA (nuclead), Slime layer capsule.
3) They lack a nucleus but contain a circular chromone of DNA.
4) Some bacteria can carry out photosynthesis but most feed off other living or dead organisms.
5) example:-
a) Lactobacillus bulgaricus- a rod-shaped bacterium used in the production of yogurt from milk.
b) Pneumococcus- a spherical bacterium that acts as the pathogen causing pneumonia.

Question 5

Protoctists

Answer 5

1) microscopic single-celled organisms with a nucleus.
Some like ,
Amoeba:- - lives in pond water
- have features like an animal cell
Chlorella:- have chloroplasts
- and are more like plants
A pathogenic example:- Plasmodium - responsible for causing malaria.
Plasmodium:- A single-celled protoctist that causes the disease known as malaria. Spreads from person to person by a female mosquito as they suck blood. Plasmodium invades the red blood cells of the host and feeds on the cytoplasm.

Question 6

Viruses characteristics

Answer 6

1) these are small particles , smaller than bacteria
2) They are parastic- can reproduce only inside living cells; they infect every type of living organism.
3) They have a wide variety of shapes and sizes.
4) they have no cellular structure but have a protein coat and contain one type of nucleic acid either DNA or RNA.

Question 7

Name 3 types of viruses, their diseases and affected organisms.

Answer 7

Virus————– Disease———————Affected Organism

1) TMV —– Discoluration of tabocco leaves —-Plants
2) HIV — AIDS— Humman’s immune system
3) Influenza virus—- Flu —– Human’s respiratory system

Question 8

what do the following keywords stands for?
HIV
AIDS
RNA
DNA
TMV

Answer 8

HIV- Humman Immunodeficiency Virus
AIDS- Acquired Immune Deficiency Syndrome
RNA- Ribo Nucleuic Acid
DNA- Deoxyribo Nucleuic Acid
TMV- Tobacco Mosaic Virus

Question 9

Define Pathogens

Answer 9

A pathogen is a micro-organism that causes a disease in its host. The host may be an animal, a plant or even another microorganism.
Examples:-
1) Fungus - Athlete foot and Fusarium (the fungal pathogen that infects the wheat crop.
2) Bacterium- Pneumococcus- causes Pneumonia
3) Virus- Influenza virus- causes flu in humans
4) protoctist- plasmodium- causes malaria