Unit 3 Flashcards
(89 cards)
1
Q
Species
A
A group of living things that can breed to produce fertile offspring
2
Q
Biodiversity
A
The variety of living things in a defined area
3
Q
Population
A
All the organisms of the same species living in the same area
4
Q
Ecosystem
A
All the organisms living in an environment and the non living components that the organisms react which
5
Q
Habitat
A
The place where an organism lives
6
Q
Producers
A
A plant at the beginning of a food chain
7
Q
Consumer
A
An animal in a food chain that eats something else
8
Q
Herbivore
A
Only eats plants
9
Q
Carnivore
A
An organism that only eats animal matter
10
Q
Omnivore
A
An organisms that eats both plants an animals
11
Q
Predator
A
An organism Hunts prey
12
Q
Prey
A
An organism that’s hunted by predators
13
Q
Community
A
All the organisms in an ecosystem
14
Q
Niche
A
The role of an organism in a community
15
Q
Intra specific competition
A
When individuals of the same species compete for all the same resources
More intense than inter specific
16
Q
Inter specific competition
A
When individuals of different species compete for some of the same resources
17
Q
Non living components of an eco system
A
Light
Water
Rock
Soil
18
Q
Examples of Living components
A
Animals
Plants
Bacteria
19
Q
What do plants compete for
A
Light
Water
Space
20
Q
What do animals compete for
A
Food
Water
Shelter
Mates
21
Q
Arrows in a food chain represent ?
A
The flow of energy
22
Q
Biotic factor
A
A living factor that influences an ecosystem
23
Q
Abiotic factors
A
A non living factor that influences an ecosystem
24
Q
Quadrat
A
Equipment used to estimate the number of plants in a given area
25
Pitfall trap
Equipment used to count an estimate the number of **small animals** in a given location
26
Paired statement key
A set of **paired questions** that allow **living things to be identified**
27
Indicator species
Species that **determine environmental quality/pollution** by their **presence and absence**
28
Light intensity
The amount of light available
29
Soil moisture
The water content of soil
30
Name abiotic factors
Light intensity
Moisture
PH
Temperature
31
Name biotic factors that influence an ecosystem
Competition
Disease
Food availability
Grazing
Predation
32
Factors that can increase bio diversity
Increased moisture levels
Warm temperature
Good food availability
33
Factors that can decrease biodiversity
Extreme temperature
Overgrazing
Too many predators
34
what do you use to measure light intensity
Light meter
35
How to measure soil moisture
Moisture meter
36
How to measure soil PH
PH meter
37
Sources of error with a light meter and how to prevent
User could **cast a shadow over the meter**
Prevent this by **standing to one side** to prevent casting a shadow
38
Sources of error with moisture/PH meter and how to prevent
**Soil left on probe** from previous readings
Prevent this by **wiping the probe dry** between readings
39
Sources of error with quadrats
Human judgment- struggling to decide if a plant is inside or outside the quadrant
Prevent by using basic rules to keep counting consistent
40
Sources of error with pitfall traps and how to prevent
Animals may escape or get eaten
Prevent by covering the trap and keeping it hidden from predators.
41
Photosynthesis
A **two stage process** in plants to **make sugar** from **water and carbon dioxide** using **light energy**
42
What is the first stage of photosynthesis called
Light reactions
43
Chlorophyll
A chemical found in **chloroplast** that is able to **trap light energy**
44
what is the second stage of photosynthesis called
Carbon fixation
45
What is sugar converted into for storage
Starch
46
What is sugar converted into for structural uses
Cellulose
47
What is a limiting factor
A **factor or substance** that **prevents a chemical reaction** from happening quick
48
What happens during step one (light reactions) of photosynthesis
-**Light energy** from the sun is **trapped by the chlorophyll**
-Some light energy is **converted into chemical energy**
-the remaining light energy is used to **split water into hydrogen and oxygen**
**Oxygen diffuses out the cell**
49
What happens during stage 2 (carbon fixation) of photosynthesis
-The **ATP and hydrogen** generated from stage one is combined with **carbon dioxide from the air**
-They are then **converted into sugar** during a **series of enzyme controlled reactions**
50
What are the 3 uses of sugar made by photosynthesis
Respiration to produce ATP
Storage as starch
Cellulose for cell wall
51
What is a pyramid of numbers
A diagram of the **total numbers of organisms** at each stage of a food chain
52
Pyramid of energy
A diagram of the **total energy contained within each stage** of the food chain
53
How to tell the difference between pyramid of energy and pyramid of numbers
Pyramids of numbers can be irregularly shaped
Pyramids of energy is always pyramid shaped
54
Three ways energy can be lost along a food chain
Heat
Movement
Undigested materials
55
Food yield
The amount of food grown from crops
56
What is a fertiliser
Mixture of chemicals used to increase crop yield
57
Nitrates
A type of chemical important for amino acids and protein formation
58
Pesticides
Chemicals that kill animals or weeds that harm crops
59
Amino acids
The **building blocks of proteins**
60
Leaching
The process of **fertilisers** being **washed from the fields** into **water supplies**
61
Algal bloom
A sudden increase in algal population
62
Genetically modified
A living organism that has had new genes added to it artificially
63
Toxicity
A measure of the harmfulness of a chemical to living things
64
Biological control
Using living organisms to control pests. For example ladybirds to eat greenfly
65
How to increase food yield
Use fertilisers
Use GM crops
66
How to prevent pests from damaging crops
Pesticides
GMcrops
Biological control
67
Disadvantage of fertilisers
They can leach into fresh water
68
Disadvantage of pesticides
Bioaccumulation in food chains.
69
Disadvantage of GM crops C
Expensive
70
Disadvantage of biological control
Difficult to manage
71
Steps of fertilisation
1.Fertilisers are added
To soil to **increase the nitrate content of the soil**
2. Nitrates dissolved in water are **absorbed into plants**
3. The nitrates are used to make **amino acids** which combine to make **plant protein**
4.animals eat plants or other animals to **obtain amino acids** for **protein synthesis**
72
Steps of leaching
1.fertilisers leach into water
2. There is an **algal bloom** in the water
3.algal blooms **block the light, which kills the plants**
4. Dead plants feed bacteria which causes an huge **increase in bacteria**
5. The bacteria uses a **large amount of oxygen** which reduces **oxygen availability** for other organisms like fish
73
Bioaccumulation
Chemicals in pesticides can **accumulate in the bodies of organisms** and gets **passed along the food chain**. The toxicity **increases** as it gets passed along the food chain **which can be lethal**
74
Mutation
A random change to genetic material
75
Alleles
Different versions of the same gene (brown eyes and blue eyes for example)
76
Variation
The differences within a population
77
Natural selection
The process by which evolution occurs
78
Speciation
The process that results in a new species
79
Isolation barrier
A geographical, behaviour or ecological mean that separates two populations
80
Selection pressure
A change in the environment for a living things eg a new predator in the ecosystem
81
Adaption
An **inherited characteristic** that makes an organism well suited for survival in its environment
82
Factors that can increase mutation rate
Processed food
Some chemicals
Radiation
83
Why is variation important
It’s important as it allows a population to evolve to **suit any new selection pressures**
84
Steps of natural selection
1. Species produce **more offspring** than the environment can sustain
2. The best **adapted** individuals in a population **survive**
3. The survivors **reproduce** and pass on **favourable alleles** with the selective advantage
4.the favourable alleles **increase in frequency** within the population
85
Steps of speciation
1. Part of a population becomes isolated by an **isolation barrier**.
2. Over a long period of time, **different mutations** occur in each sub population
3.there will be **different selection pressures** acting in the two groups.
4.Each sub population evolves until they become so **genetically different** that they are **two different species**
86
The 3 types of isolation barriers
Geographical
Ecological
Behavioural
87
Examples of geographical barriers
Rivers
mountains
Oceans
88
Examples of ecological barriers
PH,
Different habitats
Salinity
89
Example of behaviour barrier
Different mating behaviour
