Living Things Flashcards
Name the eight characteristics of living things
Movement, respiration, sensitivity, homoeostasis, growth, reproduction, excretion, nutrition
Why do animals need nutrition?
To provide them with energy and the raw materials for growth and repair
What is respiration?
Respiration is the process of transferring energy from glucose. It goes on in every cell in your body.
There are two types of respiration: aerobic (with oxygen), and anaerobic (without oxygen)
What is excretion?
Removal of waster products such as carbon dioxide and urine form the body.
What is sensitivity?
The ability to react to stimuli or changes in their surroundings
What is meant by movement?
Living things can move and change their positions
What is homeostasis?
They can control their internal conditions including temperature and water content
What is reproduction?
Living things have to have offspring (children) in order for their species to survive
What is meant by growth?
Getting bigger and developing into adult form
What are the five kingdoms?
Plants, animals, fungi, bacteria, protoctists
Describe the plants kingdom.
Give examples.
- they are multicellular
- they have chloroplasts so they can photosynthesise
- their cell walls are made of cellulose
- they store carbohydrates as sucrose or starch
Examples
Flowering plants like:
-cereals (e.g. maize)
-herbaceous legumes (e.g. peas and beans)
Describe the animals kingdom.
Give examples.
- they are multicellular
- they don’t have chloroplasts and they can’t photosynthesise
- they don’t have cell walls
- most have some kind of nervous coordination this means that they can respond rapidly to changes in their environment
- they can usually move around from one place to another
- they often store carbohydrate in the form of glycogen
- they need to eat other living things
Examples
- mammals (e.g. humans)
- insects (e.g. houseflies and mosquitos)
Describe the fungi kingdom.
Give examples.
-some are single celled
-others have a body called and mycelium, which is made up of hyphae (thread like structures). The hyphae contain lots of nuclei.
-they can’t photosynthesise
-their cell walls are made of chitin
-most feed by saprotrophic nutrition:
They secrete extracellular enzymes into the area outside the body to dissolve their food,so they can absorb nutrients.
-they can store carbohydrate as glycogen
-no stems, roots, or leaves
Examples
- yeast - this is a single celled fungus
- mucor - this is multicellular and has a mycelium and hyphae
Describe the protoctists kingdom.
Give examples.
- they are single celled
- they are usually micro organisms
- some have chloroplasts and are similar to plant cells
- others are more like animal cells
- they are aquatic
Examples
- chlorella (plant-cell-like as it has chloroplasts)
- amoeba (animal-cell-like) - lives in pond water
Describe the bacteria kingdom.
Give examples.
- these are single celled and microscopic
- they don’t have a nucleus
- they have cell walls
- they have cell membranes
- they have a circular chromosome DNA
- some can of photosynthesise
- most bacteria feed off other organisms - both living and dead
Examples
- lactobacillus bulgaricus - can be used to make milk go sour and turn into yogurt. It is rod-shaped.
- pneumococcus - spherical - causes pneumonia
Draw a labelled diagram of an animal cell
See page 2 of the CGP textbook Include: Nucleus Cell membrane Cytoplasm Ribosomes Mitochondria
Draw a labelled diagram of a plant cell
See page two of the CGP textbook Include: Nucleus Cell membrane Cytoplasm Ribosomes Mitochondria Chloroplast Vacuole Cell wall
What is the nucleus?
An organelle which contains genetic material that controls the cell’s activities. It is surrounded by its own membrane.
What is the cell membrane?
This membrane forms the outer surface of the cell and controls the substances that go in and out.
What is the cytoplasm?
A gel like substance where most of the cell’s chemical reactions happen. It contains enzymes which control these reactions.
What are ribozymes?
Small organelles where proteins are made in the cell.
What are mitochondria?
Small organelles where most of the reactions for aerobic respiration take place. Respiration transfers energy that the cell needs to work.
What are chloroplasts?
Photosynthesis, which makes food for the plant, happens here. Chloroplasts contain a green substance called chlorophyll, which is used in photosynthesis.
What is the vacuole?
A large green organelle that contains cell sap (A weak solution of sugar and salts). It helps to support the cell.
What is the cell wall?
A rigid structure made of cellulose, which surrounds the cell membrane. It supports the cell and strengthens it.
Describe viruses
- they are NOT classified as a kingdom
- they are particles, rather than cells and are smaller than bacteria
- they can only reproduce inside living cells. A virus is an example of a parasite - it depends on another organism to grow and reproduce.
- they infect all types of living organisms
- they come in lots of different shapes and sizes
- they don’t have a cellular structure - they have a protein coat around some genetic material (either DNA or RNA).
Examples
- Influenza virus
- HIV
- Tobacco mosaic virus - this makes the leaves of tobacco plants discoloured stopping them from producing chloroplasts.
What are the levels of organisation? (in order)
Organelle, Cell, Tissue, Organ, Organ System, Organism
Describe an organelle and give an example
The tiny structures found within a cell
Eg mitochondria
Describe a cell and give an example
The most basic structure of a living organism. These are described as the building blocks of life.
Eg Epithelial cell
Describe a tissue and give an example
A group of cells working together with similar structure and function. It can contain more than one type of cell.
Eg muscle tissue
Describe an organ and give an example
It’s made up of tissues and can contain many different tissues which all work together to carry out a function
Eg stomach
Describe an organ system and give an example
Groups of different organs that work together to perform a particular function
Eg Respiratory system
Describe an organism and give an example
A complete living thing made up of many organ systems. Characterised by MRS H NERG
Eg human
Describe Prokaryote cells
-They don’t have a nucleus
-They don’t have organelles such as chloroplasts and mitochondria
-They are smaller and simpler
Eg bacteria
Describe Eukaryote cells
-They have a neucleus
-They have organelles such as chloroplasts (site for photosynthesis) and mitochondria (site for respiration)
-They are larger and more complex
Eg plant, animal, fungi, protoctists
What is classification?
Classification is sorting living things into different groups based on their different characteristics
Why is classification important to biologists?
It helps to order and categorise all different life forms and understand the relationships between them (as there are so many of them)
If you know which group an organism belongs to, you can predict certain aspects about its features.
Why are viruses not included as a sixth kingdom?
They do not have enough of the characteristics of living things (MRS H NERG)
Why are cells specialised?
Cells are specialised to carry out a particular function.
For example, red blood cells are specialised for carrying oxygen and white blood cells are specialised for defending the body against disease.
Which kingdoms are eukaryotes?
Plants ,animals, fungi, protoctists
Which kingdoms are prokaryotes?
Bacteria
Why were some protoctists once classified as plants and others as animals?
Some protoctists have characteristics of plants (e.g. chlorella - has chloroplasts) while others (like amoeba) have characteristics of animals. However, as they are unicellular they are neither plants nor animals.
What is the name of molecule which makes plants look green?
Chlorophyll
What is the word equation for photosynthesis?
Carbon Dioxide + Water ➡️ Glucose + Oxygen
What are the reasons why viruses aren’t classed as living organisms?
- Do not respire
- Cannot reproduce without (host) cell / reproduce in (host) cell / can only reproduce within an organism
- Do not move
- Do not sense
- Do not excrete
- Do not grow
- Do not feed / do not need nutrition
- Do not control their internal conditions
- Are not cellular
What are the structural differences between a virus and bacterium?
- Bacteria and bigger / viruses are smaller
- Bacteria have a cell membrane
- Bacteria have a cell wall / viruses have protein coat / viruses have capsid / viruses have envelope
- Bacteria have flagellum
- Bacteria have plasmids
- Bacteria have cytoplasm
What do chloroplasts do?
a chloroplast /chlorophyll captures energy from sunlight and convert it into glucose by photosynthesis
Is it correct to describe mosquitoes as the cause of malaria?
Yes, because the protoctist plasmodium (which causes malaria) infects humans, and is spread by mosquitoes. However, mosquitoes do not create the malaria, they just spread it and therefore are indirectly accountable for malaria.
Draw and label a typical bacterial cell, with features that are always present ans sometimes present.
NO NUCLEUS Include: Always present: -cell wall -cytoplasm -cell membrane -chromosome containing genes Sometimes present: -capsule -plasmid - contains a small amount of additional DNA -flagella -(plural of flagellum)
Draw and label a typical fungal cell.
Include
- cell wall(chitin)
- cell membrane
- mitochondria
- nucleus
- cytoplasm
- ribosome
Define a pathogen
Something which causes disease in other organisms.
Which kingdoms contain pathogenic organisms?
Protoctists, fungi, bacteria
Viruses are pathogens but they are not classified as living things
Which is the smallest pathogen?
Viruses
What illness does the HIV virus cause?
AIDS
Describe the structure of a virus.
Virus particles have a variety of shapes. They do not have a cellular structure. Instead, they have a core of genetic material surrounded by a protein coat. Their genetic material can be DNA or RNA, but not both.
What illness does influenza cause?
Flu
The tobacco mosaic virus prevents the formation of chloroplasts in tobacco plant cells. What effect will this have on the plant.
It will mean the plant can’t photosynthesise and will lack nutrition. It will get yellow discoloured leaves because it doesn’t have enough chloroplasts.
Viruses are parasitic. What does this mean?
They can only reproduce inside the living cells of an organism that they have infected.
Why are viruses described as particles rather than cells.
They have no cellular structure.
Why are viruses unable to respire?
They don’t have any mitochondria
Give one piece of evidence that suggests viruses may be living.
Contains genetic material and it can reproduce
How do viruses cause disease?
They take over the genetic material of your cells and instruct the host cell to make copies of the virus until the cell burst, releasing millions of copies of the virus to infect other cells. In this way viruses kill infected cells, spread and damage body tissues. The way your body reacts to this cell damage gives you the symptoms of disease.
