Science Semester 1 Exam 2025 Y9 Flashcards
(17 cards)
What is a disease?
ANy change that distrupts the function of an individual in some way. It causes harm to the indivdual.
What are the 2 types of diseases?
Infectious and non infectious.
What are microbes
Tiniy living things that can only be seen under a microscope.
What are the five types of microbes?
Protozoans, prarasite, Bacteria, Viruses, Fungus, PRION.
Recall one similarity and wo differences between pathogenic bacteria and pathogenic fungi
Similarity: Both living organisms
Differences: Cause different disease and fungi is eukaryotic.
What is Bacteria
Simple unicellular organisms that lack a nucleua. They are prokaryotes
What is a virus?
Bundles of genetic material surrounded by a shell of proteins and fats
Fungi
Eukaryotic organisms with a special compound called chitin in their cell walls
What is a parasite
Not normally thought of a smicobes, because they can be see with the naked eye. But they are often indentified by their eggs, which are microscopic.
What is protozoa
Single celled organisms that belong to the group protists, which are neither plants nor animals and lack a cell wall.
What are PRIONS
Infectious proteins
What is the role of the immune system
The immune system is a netwok of cells , tissues and musles that work together to fight infections and diseas.
Explain the first line of defence.
The first line fo defence is maade up fo barriers that prevent pathogens for entering the body. The include the skin, celilia, salivia and the nasal hairs.
Explain the second lien of defence.
The second line of defence is made up from general responses that fight pathogens, e.g. inflammation and fevers.
Explain the third line of defence.
The third line of defence helps build long term immunity against specific pathogens. The lymphocytes (white blood cells) do this. There are two types, b and t cells
B cells
they have proteins on their outer bodies (antibodies)
Antibodies
they match certain proteins of antigens
