Bio3.1- Flashcards
1
Q
Characteristics of Microorganisms (6)
A
- Typically single-celled organisms
- Very important to life on Earth
- Include bacteria, viruses, and some fungi
- Can only be seen through microscopes
- Humans culture microorganisms
- Humans can see colonies without microscopes
2
Q
Bacteria (6)
A
- 0.2-2.0 µm (micrometer) in diameter
- Found in the environment and our bodies
- Many shapes and sizes
- All single cells
- Feed, respire, and produce waste carbon dioxide and other waste products
- Grow and then reproduce by splitting in two
3
Q
A bacteria is about – the size of a human cell.
A
1/10
4
Q
Bacteria’s features (6: All have+many have)
A
All have (+cell membrane):
1. a loop of genetic material carrying information about making new bacteria (no nucleus)
2. cell wall (determines the cell’s shape—structure is different from a plant’s cell wall)
3. cytoplasm: holds internal components of the cell in place (+site for chemical reaction)
Many have:
4. plasmids: extra pieces of genetic information
5. slime capsule: helps from drying out and from attack by other cells
6. flagella: movement (beat)
5
Q
Fungi (5)
A
- some are microorganisms and others grow very big
- some are made up of hyphae
- hyphae absorb food from the surroundings
- cell walls are made up of chitin
- reproduce by making spores
6
Q
feature of hyphae
A
tangle of microscopic threads
7
Q
Yeasts (3)
A
- single cells
- 4 µm in diameter
- reproduce by splitting into two
8
Q
Viruses (4)
A
- 0.1-0.01µm in diameter (1/1000 of a human cell)
- found everywhere
- genetic material inside protein coat
- invade bodies of living organisms & turn them into virus-making factories
9
Q
Scientists estimate there are — bacteria on Earth
A
5 million trillion
10
Q
- Yeast makes bread –.
- When yeast cells are given —, they respire and grow fast, producing lots of waste carbon dioxide.
- Carbon dioxide makes the bread –, It gets bigger and its texture gets lighter.
- When we cook the bread, the — - although cooking –.
A
light and delicious; sugar, warmth, and air; dough rise; bubbles of gas get even bigger; kills the yeast
11
Q
Yoghurt is a creamy solid made by —, which feed on the - in the milk. The bacteria produce –. This – the milk and gives yoghurt its – taste. The bacteria which turn milk into yoghurt also help to keep —, because they —.
A
mixing warm milk with bacteria; sugar; lactic acid; solidifies; sharp, tangy; the yoghurt good; stop other bacteria growing
12
Q
Cheese, like yoghurt, is made by the—. The bacteria used in making cheese produce —, making the milk separate into —-. The curds may be mixed with — and used when they are fresh. They can also be mixed with —, and then pressed and left to dry for weeks, months or even years.
A
reaction of bacteria with milk; lots of lactic acid; solid curds and liquid whey; seasoning and herbs; salt and other bacteria
13
Q
Antibiotics (=—):
Founder
First
Target
A
medicines that stop bacteria from growing, or kill them, curing the infectious diseases that they cause;
early 20th century Alexander Fleming
penicillin (a substance made by the mould that stopped the bacteria growing)
Bacterial structures such as cell walls ( X work against viruses and human cells)
14
Q
Scientists change bacteria so that they make –. The microorganisms grow in huge metal tanks called -.
A
human insulin; fermenters;
15
Q
What is the use of human insulin?
A
They are needed to keep people with diabetes, healthy.
16
Q
What do fermenters do?
A
Grow micoorganisms (Separate the insulin from the microorganisms and the liquid they grew in.)
17
Q
In the - century, a - scientist called – was –. This is because—-. His work (experiment date: 1881 May) helped everyone accept the —-.
A
19; French; Louis Pasteur; determined to find the cause of infectious diseases; 3 of his children died of infectious diseases; germ theory of disease
18
Q
Germ theory of disease
A
The idea that infectious diseases are caused by microorganisms passed from one organism to another.
19
Q
Pasteur’s 6 experiment steps
A
- Hypothesis
- Problems
- Investigation
- Prediction
- Observations
- Conclusions
20
Q
Pasteur’s hypothesis
A
Anthrax is caused by a germ passed from one animal or person to another.
21
Q
Pasteur’s idea
A
He wanted to grow anthrax germs, weaken them, then inject them into sheep. He thought this vaccine would protect the sheep against anthrax.
22
Q
Pasteur’s problems
A
- He struggled to grow anthrax germs in his laboratory, and then found it difficult to make a vaccine from them.
- His rival (Jean-Joseph Toussaint) had already made a vaccine by a different method, without proving it worked.
(Hippolyte Rossignol) A vet did not believe germs caused diseases. He challenged Pasteur to prove his theory by a public test.
23
Q
Pasteur’s investigation
A
Step 1: Pasteur gave healthy sheep, cows and goat his anthrax vaccine.
A similar group of healthy animals were not given the vaccine.
Step 2: All the animals were infected with live anthrax from diseased animals.
24
Q
Pasteur’s prediction & observation
A
vaccinated animals will survive, the unvaccinated will not.
As predicted.
25
Pasteur's Conclusions
the germ theory of disease was correct
Anthrax was caused by germs which spread from one animal to another
we can cure the diseases by attacking the microorganisms which caused them
26
Scientific hypotheses can be --- by evidence from an
--.
supported or contradicted; enquiry
27
It is possible to predict the --- based on your scientific knowledge and understanding.
outcome of a scientific enquiry
28
Direct contact
1. Some microorganisms passed from one person to another by direct contact with skin/ with objects that ppl had coughed or sneezed upon.
2. You transfer microorganisms to the mouth, eyes, or other parts by touch.
28
Four ways that disease passing microorganisms can spread from person to person
Direct contact, droplet infection, break in the skin, contaminated food and drink
29
Droplet infection
1. Tiny droplets of disease-causing microorganisms are forced out of your nose and mouth when you breathe, talk, and sneeze.
2. Other people breathe in the droplets and take microorganisms to their body.
30
Contaminated food and drink
1. Water contaminated by human waste/ raw/ undercooked food may contain disease-causing microorganisms.
2. The microorganisms are directly taken into the body.
31
Break in the skin
Some microorganisms get straight to the bloodstream through cuts and breaks in the skin that include animal bites, scratches, and needle punctures.
32
COVID-19 is caused by- and -
droplet infection and direct contact
33
6 ways to reduce the spread of COVID-19
1. Wash your hands (use antiseptic hand gel)
2. Wear a face mask
3. Keep a distance between you and other ppl
4. Meet as few ppl as possible (meet outdoors)
5. Stay at home if you feel ill
6. Cough or sneeze into your elbow or a tissue
34
Science is applied across societies to help solve ---.
real-life problems like disease control
35
People use scientific understanding to ----.
explain how to prevent the spread of disease
36
Plants take --- and use them to build new plant cells.
water and mineral salts
37
Decomposers (3 ex.)
Microorganisms (fungi, bacteria, flies...) that feed on dead bodies, fruits, droppings and other food.
38
Decomposers break it all down, ---. They release -- and ---, in a form that plants can use. This prevent ---.
digesting it and using some of the nutrients to grow and reproduce; waste products; some of the digested material back into the soil; a build-up of materials, and animal droppings
39
2 usages of decomposers
make compost (to grow food) and treat sewage
40
Making compost: we use decomposers to break down ---. In the right conditions, bacteria and fungi break this down into---. A compost bin lets you ---. Adding compost to your soil ---, so your plants grow bigger and better.
our kitchen and garden waste; a brown, soil-like substance called compost; control the conditions to make good compost as quickly as possible; puts back nutrients
41
Treating/breaking down sewage: the world population keeps growing and the more people there are, the more ---. Whether you use flushing toilets or a pit latrine, you rely on --- so it does not ---.
bodily waste is produced; microorganisms to decompose the waste and break it down; damage the environment
42
Fungi and bacteria break down ---.
droppings, fruit, leaves and the dead bodies of animals and plants
43
- affects the speed of decomposition. -- stop the decomposers from working.
Temperature; Very cold temperatures
44
Decomposition happens more slowly at --.
low temperatures
45
Decomposers feed on material and --. This means that ---. To observe how quickly the decomposers are working, measure --.
digest it; the material being decomposed will lose mass; any changes in mass
46
Mould -- on the potato in the coolest place.
grows more slowly
47
You make conclusions by --. You need to be able to --- of the conclusions.
interpreting results; identify and explain the limitations
48
Food chains
simple models that biologists use to show the feeding relationships between the organisms in a habitat
49
Food web
a way of modelling feeding relationships which links several food chains together
50
producer
first organism in a food chain
often a plant (trap energy from the Sun & make food by photosynthesis)
make its own food
51
herbivores
animals that only eat plants
52
carnivores
animals that only eat other animals
53
The arrows in a food chain show -----.
the transfer of biomass from 1 organism to the next in the chain
54
Food chain may have---.
2-5 links
55
At each stage, some material ---. Energy is transferred from the living organisms to ---. The length of a food chain is limited by ---- to the organisms at the top: the longer the chain, the ---.
cannot be digested and is lost as waste; their surroundings or used to move about; the biomass transferred through the chain; less biomass reaches the organism at the top
56
Most biomass will lose bc (3)
1. Organisms do not eat every single part
2. Bits that do eat may not be absorbed
3. Release energy through respiration
57
Decomposers--- to the soil to be recycled. These nutrients are --- and used to help build new plants, the starting point of ---.
break down plants and animal material and return nutrients; taken up from the soil; a new food chain
58
Food webs and chains are---.
models of feeding relationships between organisms
59
Abiotic
sth that is non-living
60
3 examples of abiotic factors
rock, soil or sand making up a landscape; temperature; water
61
'rock, soil or sand making up a landscape' example
affect the type of organisms that survive there (difference between rocky mountainside and rich soil of a river valley)
62
'temperature' example
difference between a hot desert and a subzero environment
63
'water' example
amount of water available in an ecosystem affects all live
64
3 importance of water
1. 71% of the surface of the Earth is covered in water (96.5% is in the ocean/saltwater)
2. Water fills our cells: up to 60% of an adult is water (90% of jellyfish are water)
3. Plants need water to transport food &mineral salts around their bodies, make food in photosynthesis, for support
65
3 properties of water
1. water is a very good solvent
2. it takes a lot of energy to heat the water up and it cools down very slowly
3. solid ice floating on top of liquid water acts as an insulating layer that stops water below from freezing
66
'Water is a very good solvent' why? (3)
1. All the chemical reactions of life take place in solution in water
2. Sea water contains dissolved sodium chloride and other mineral salts
3. Blood contains dissolved food molecules, mineral salts, chemical messenger and blood cells
67
'it takes a lot of energy to heat the water up and it cools down very slowly'
so that---
the temperature is very stable and organisms do not need to cope with big temperature changes
68
'solid ice floating on top of liquid water acts as an insulating layer that stops water below from freezing' so that---
organisms can survive in the water until warmer weather returns
69
Difference between steam and water vapour
steam: over 100 degrees
water vapour; below 100 degress
70
water cycle (4 parts)
the process by which fresh water moves constantly through the environment over time (evaporation, condensation, precipitation, collection)
71
Evaporation:---
Energy from the sun -----. Some of the water -. It turns from a liquid to ---.
The process by which a liquid changes state to become a gas as it warms up;
heats up the water in puddles, streams, lakes, rivers and oceans; evaporates; a gas called water vapour
72
Condensation:---
Water vapour rises up into the sky. The higher it gets, the ---. When the water vapour cools down, ---. The small drops of liquid water ---. These clouds can --- up in the atmosphere.
The process by which a gas changes state to become liquid as it cools;
cooler it is; it turns back into liquid water; form clouds in the sky; travel thousands of miles
73
Precipitation:---
The water droplets in the clouds ---. When they get big enough, they ---. Precipitation may be ---, depending on the ---.
water droplets that become too heavy to remain in a cloud;
get bigger and heavier as more water condenses; fall back down to the Earth as precipitation; rain, snow, hail or sleet; temperature of the air
74
Collection:
Precipitation collects ---, and the whole cycle starts again. It may fall directly into -- such as oceans, lakes and rivers. The precipitation may --- it cannot travel through, and be stored there. Water --- is called groundwater. Water that --- , is called runoff.
in bodies of water; open water; soak through the ground until it reaches a layer; held in the soil and stored underground; cannot be absorbed by the ground, but runs off the surface into streams and river
75
How do plants play a part in the water cycle?
During the process of transpiration, plants absorb water from the soil through their roots. The water travels up the xylem tissue and evaporates from the surface of the leaves.
76
How do animals play a part in the water cycle?
Animals take in water when they drink and in their food. They lose water when they breathe out, when they produce urine and faeces, and when they sweat. This water evaporates and forms water vapour in the air.
77
Water is constantly --- in the water cycle
recycled through the environment
78
Water from the surface of the Earth --- in the air. This -- to form -- (clouds). The water droplets fall ---, which goes into the open water.
evaporates to form water vapour; cools and condenses; water droplets; as precipitation into open water, groundwater or run-off
79
Global warming
rising of our entire planet's average temperature
80
What is the cause of global warming (2)?
1. Burning of fossil fuels produces carbon dioxide, which warms Earth, causing climate change
2. Deforestation (more carbon dioxide is released and less is absorbed)
81
Effects of global warming (4)
1. loss of sea ice
2. extreme flooding and droughts
3. ^ thus sea level rise
4. seasons unpredictable
82
Prevention of global warming (3)
1. Use energy saving electricity equipments
2. use public transportation or cleaner ways of transportation
3. recycle household garbage
83
Most of the fresh water is ---.
stored as ice in the glaciers and ice caps
84
3 reasons to why sea level rises
1. The polar ice caps and glaciers are melting fast into the sea
2. The sea is getting warmer so it expands (thermal expansion)
3. The warmer temperature causes more water to evaporate into the air, forms bigger clouds and causes extreme rainfall over the oceans.
85
The increase in the surface temperature of the Earth means that --- into the air. Warmer air holds more water vapour. As it --, we get --- often lead to -.
Flooding destroys homes, washes away soil and causes loss of life. The most extreme rainfall happens over the ---, so --- from flooding.
more water evaporates from the surface; rises and cools; bigger clouds and bigger rainstorms that; flooding; oceans and coastal areas; coastal areas suffer most
86
At some places, water evaporates from the soil but any clouds are ---.
These droughts have always happened, but now they are --. When it does rain, it is a --. Most of the water --- into the soil. The water left in
the soil ---, once the rain stops falling.
blown away so no rain falls; lasting for longer ; violent downpour; runs off and does not soak; evaporates quickly in the warmer climate;
