Topic 7 - January Yr12 Flashcards
1
Q
How to measure Light?
A
Light meter
2
Q
How to measure Temperature?
A
Thermometer
3
Q
How to measure wind speed?
A
Anemometer
4
Q
How to measure pH?
A
pH meter
5
Q
What 3 ways can substances move in and out of cells?
A
Diffusion
Active Uptake
Osmosis
6
Q
What is Osmosis?
A
The movement of water molecules from a dilute solution to a more concentrated solution through a selectively permeable membrane
7
Q
What happens if cells lose too much water?
A
They become plasmolysed and shrivel up
8
Q
What happens if cells get too much water?
A
They swell and burst
9
Q
What happens when Plant Cells lose water?
A
They become plasmolysed and lose their turgor, becoming flaccid
10
Q
What 4 reasons make water very important for plants?
A
Support
Transport
Transpiration
Photosynthesis
11
Q
What is transpiration?
A
Evaporation of water from spongy mesophyll followed by diffusion through air spaces and stomata
12
Q
What is the Transpiration stream?
A
The continuous movement of water in to, through and out of the plant
13
Q
How to measure speed of water uptake with Bubble Potometer?
A
Record initial position of bubble
After a certain period of time, record final position of bubble
Calculate distance moved by bubble per minute
14
Q
What 4 environmental factors affect transpiration rates?
A
Temperature
Wind speed
Humidity
Surface area
15
Q
How to measure effect of Temperature on Transpiration rate using Bubble Potometer?
A
Place the shoot in areas where the temperature differs
16
Q
How to measure effect of Wind Speed on Transpiration rate using Bubble Potometer?
A
Using a fan with different settings
17
Q
How to measure effect of Humidity on Transpiration rate using Bubble Potometer?
A
Cover the shoot with a polystyrene bag
18
Q
How to measure effect of Surface Area on Transpiration rate using Bubble Potometer?
A
Have shoots with different sizes or number of leaves
19
Q
What are the 2 main functions of the Circulatory System?
A
Transport of materials
Protection against disease
20
Q
What is plasma?
A
Plasma is the liquid part of the blood
21
Q
What 5 things does plasma transport?
A
Cells Digested food molecules CO2 Hormones Urea
22
Q
What is the function of the Hepatic portal vein?
A
Transports dissolved food from intestine to liver
23
Q
Heart disease cause, result?
A
- Coronary arteries blocked by high cholesterol
- Less oxygen and glucose to heart; less respiration; heart cells die; heart stops beating
24
Q
Strokes cause, result?
A
- Blood vessel in brain blocked with cholesterol
- Less oxygen and glucose to brain; less respiration; brain cells die; reduced brain/body function
25
What 2 types of factors increase chances of circulatory disorders?
Genetic
| Lifestyle
26
How does plasma convert to tissue fluid to lymph to plasma?
Plasma diffuses through capillary walls, in to tissue, becomes tissue fluid. Tissue fluid too far away from capillary, diffuses in to Lymphatic vessels, becomes lymph. Eventually drains back in to circulatory system, becomes plasma
27
Give 3 bacterium?
- Salmonella
- Gonorrhoea
- Tuberculosis
28
Give 3 viruses?
- HIV
- Measles
- Influenza
29
Give a fungi?
Athletes foot
30
How does salmonella spread? How is prevented or treated?
- Contaminated food
- Cook food thoroughly
- Antibiotics
31
How does gonorrhea spread? How is prevented or treated?
- Sexual contact
- Using a condom
- Antiobiotics
32
How does tuberculosis spread? How is prevented or treated?
- Droplet Infection
- BCG Vaccination
- Antiobiotics
33
How does HIV spread? How is prevented or treated?
- Exchange of body fluids
- Using a condom
- No cure
34
How does measles spread? How is prevented or treated?
- Droplet infection
- Prevented by MMR vaccination
- No treatment
35
How does influenza spread? How is prevented or treated?
- Droplet infection
- Flu vaccination
- Antivirals
36
How does athletes foot spread? How is prevented or treated?
- Contact
- Avoid contact of areas where spores are likely
- No treatment
37
Give 3 conditions microbes need to survive?
- Energy
- Oxygen
- Moisture
38
Who was Louis Pasteur? What did he do?
Scientist who disproved theory of Spontaneous Generation
39
Give 3 defences your body has against infection by microbes?
Blood clotting
Mucous membranes
Anti septic fluid in eyes
40
Give the 2 types of white blood cell?
Phagocyte
| Lymphocyte
41
What is phagocytosis?
This is when a phagocyte engulfs and digests microbes using enzymes
42
What do lymphocytes do?
They detect antigens on microbes and produce antibodies in response
43
What are antibodies?
These are produced by lymphocytes and attach to antigens on microbes.
44
What 2 things can antibodies do?
- Burst the microbe
| - Clump microbes together for phagocytosis
45
What are memory cells?
They are produced by white blood cells which remain in the persons blood for the rest of their life, making them immune to a particular disease after infection
46
What is immunity?
This means their antibody level is high enough, or can be produced to a high enough level quickly, to destroy a certain microorganism should it enter the body
47
What is active immunity and name 2 ways it can be achieved?
Active immunity is when a persons antibody levels reach a high enough level to destroy a certain microorganism, and remain high enough to destroy it if a re infection occurs in the close future
- Infection
- Vaccines
48
What is a vaccination?
This is when dead or modified pathogens are injected into the body. Antibodies are produced and the pathogens are destroyed. Memory cells are then created and now the person is actively immune to that particular microbe
49
What is Passive Immunity?
When you are given antibodies and become immune, rather than have the body produce them like in Active Immunity
50
Give 2 problems with passive immunity?
- Only short term immunity achieved, antibody levels drop quickly
- No memory cells produced
51
Give 3 ways passive immunity can be achieved?
- Injections
- Pregnant mothers placenta
- Breast Feeding
52
What are antibiotics?
Antibiotics are chemicals produced by fungi which can be used to combat bacterial infections
53
Who discovered antibiotics?
Alexander Fleming
54
What are antibiotics like penicillin produced in?
Bio digester / Fermenter
55
How is penicillin manufactured and produced?
The product in the fermenter is collected and downstreamed. Which involves extracting the product, purifying it and then packaging it for sale
56
Give 3 harms of alcohol?
Drink driving
Violence
Absence from work or school
57
Give 2 harms of drugs?
Can lead to taking more hardcore drugs
| Overdose can cause death
58
How is the brain affected by alcohol?
Slowed down reactions and lack of self control
59
How is the liver affected by alcohol?
Burns up alcohol in blood, but can be permanently damaged or even result in organ failure
60
Effects of alcohol on stomach?
Irritates it and causes vomiting
61
What is DNA stand for?
Deoxyribonucleic acid
62
What is a gene?
A short length of DNA that codes for a particular protein or certain characteristics
63
What is a chromosome?
Chromosomes are made out of a molecule called Deoxyribonucleic acid or DNA. They are located in the nucleus of living cells
64
What is DNA made out of?
Nucleotides, which are repeating sub units which are linked together in a long chain
65
Give the 4 bases found in DNA?
- Adenine
- Thymine
- Guanine
- Cytosine
66
What does Thymine always pair up with?
Adenine
67
What does Adenine always pair up with?
Thymine
68
What does Cytosine always pair up with?
Guanine
69
What does Guanine always pair up with?
Cytosine
70
When each base joins with a complementary base, what is this known as?
Base pairing
71
What is base triplet and what does it do?
A sequence of 3 bases on the coding strand of DNA forms a base triplet. This codes for a particular amino acid
72
What is Protein Synthesis?
This is when proteins are made by linking together in a chain of amino acids
73
What did Chargaff discover?
There was always an equal amount of Adenine and Thymine, and an equal amount of Cytosine and Guanine in DNA
74
What did Franklin and Williams discover?
Using X Ray Diffraction, they were able to work out the overall shape of DNA
75
What did Watson and Crick discover?
Using a process of modelling, they determined that DNA was shaped in double helix
76
Give 3 ways to measure growth other than mass and height?
Cell length
Number of cells
Dry mass
77
What are daughter cells?
New cells that are produced by cell division
78
Name the 2 forms of cell division?
Mitosis
| Meiosis
79
What is Mitosis?
A type of cell division that allows organisms to grow, repair and replace. The daughter cells produced always have the same genetic makeup as the parent cells
80
What must occur before any type of cell division?
Each chromosome must replicate itself. The copy will lie joined to the parent chromosome at a point called the centromere. This is now called a pair of chromatids
81
After the chromosomes have replicated and become a pair of chromatids, what happens next on the process of mitosis? (4 steps)
- Chromatids line up at equator of cell
- Chromatids now separate and are pulled to opposite sides of the cell
- Once chromatids reach the side of the cell, the cell divides in two
- New daughter cells contain exact same genetic makeup
82
After the chromosomes have replicated and become a pair of chromatids, what happens next on the process of meiosis?
- Chromatids line up in equator of cell
- Chromatids separate to opposite sides of the cell and the cell divides
- 2nd division occurs, as chromatids of daughter cells line up at equator again
- Each individual chromatid is separated from its paired up chromatid, and cell divides
- New cells formed each with only 23 chromosomes. These cells are now called gametes
83
What is the diploid number?
46 chromosomes
84
What is the haploid number?
23 chromosomes
85
What is a gamete?
A sex cell produced in sexual organs through meiosis, each gamete only containing 23 chromosomes
86
Name the 2 sexual organs where meiosis occurs?
Testis
| Ovaries
87
Give an alternate name for meiosis?
Reduction Division
88
What is Independent Assortment?
This is when pairs of chromosomes randomly line up in the middle of the cell before the first division in meiosis and separate, and since there are 23 pairs of chromosomes, there are millions of potential chromosome combinations that could be produced
89
What does independent assortment help achieve?
Variation in offspring
90
Give 3 differences between meiosis and mitosis?
- Mitosis occurs in nearly all body cells, while meiosis only occurs in sex organs
- Mitosis only has 1 cell division, but meiosis has 2 cell divisions
- Mitosis produces daughter cells with the same genetic makeup as the parent cells, but meiosis produces daughter cells with a unique genetic makeup
91
What is Fertilisation?
This is when a sperm cell ( gamete ) and an ovum ( gamete ) fuse together and restore the diploid number of chromosomes
92
What type of reproduction occurs in plants?
Asexual
93
Describe reproduction in plants?
- It is asexual
- Only one parent is involved, and the cells from the parent simply duplicate themselves through mitosis to form a new individual
- This is also referred to as cloning as the new individual and the parent have the same genetic makeup
94
Give 2 advantages of plant cloning?
- Allows only desirable characteristics to be produced
| - Tissue culture and produce disease free varieties
95
Give 2 disadvantages of plant cloning?
- Lack of variation can make plants susceptible to infection
| - Natural selection cannot favour the best adapted, as they are all equally adapted
96
What is Cancer?
This is when rumours are created in uncontrollable cell division
97
Give the 2 types of tumours?
- Benign, remain in one place and don't spread, may be encapsulated
- Malignant, may spread around body, create secondary tumours
98
Give 3 causes of cancer?
UV Radiation
Chemicals in cigarette smoke
Viruses
99
Give 3 cancers which can be screened for?
Breast Cancer
Cervical Cancer
Testicular Cancer
100
Give 3 treatments of cancer?
Surgery
Radiotherapy
Chemotherapy
101
What is an allele?
A particular form of gene, it may be recessive or dominant
102
What is a homozygous genotype?
When the 2 alleles for a particular gene are the same
103
What is a heterozygous genotype?
When the 2 alleles are different
104
What is a genotype?
The paired symbols for allele arrangement in an individual
105
What is a phenotype?
The outward appearance of an individual due to the genotype of a characteristic
106
How can you determine the genotype of an individual?
Back cross test is carried out. Cross breed with homozygous recessive individual. Examine the offspring. Determine genotype based on ratio of offspring
107
What is a karyotype?
A complete set of chromosomes
108
A genotype of XX in an individual means they are what gender?
Female
109
A genotype of XY in an individual means they are what gender?
Male
110
Give an example of an inherited disease?
Cystic Fibrosis
111
Give 2 effects of a random mutation in DNA?
- Change in structure of a gene
| - Change in number of chromosomes
112
A change in the number of chromosomes could cause?
Down syndrome
113
A change in the structure of a gene could cause?
Haemophilia
114
What is a genetic screening?
Testing people for the presence of a particular allele or genetic condition
115
Why is a genetic screening used?
To possibly reduce possibility of disease or conditions caused by problems with chromosomes or genes
116
What method is used to screen for Down syndrome in foetus?
Amniocentesis
117
Describe amniocentesis? ( 3 steps )
- Removing some foetal cells from the amniotic fluid surrounding the baby
- Allowing foetal cells to multiply in lab conditions
- Checking number of chromosomes in foetal cells
118
Give 3 ethical issues with genetic screening?
- If a test for Down syndrome is positive, should the mother have an abortion?
- Amniocentesis carries a 1% risk of miscarriage
- Should parents be allowed to choose to screen or not?
119
What is Genetic Engineering?
This usually involves taking a piece of DNA from a donor organism and adding it to some DNA of a recipient organism
120
Give 2 reasons Why bacteria is usually used for genetic engineering?
- Bacterial cells easily manipulated
| - Bacterial cells reproduce rapidly
121
How is insulin genetically engineered? ( 7 steps )
- Scientists cut out the insulin coding gene out of human DNA using restriction enzymes
- A plasmid is removed from bacterial cell and cut upon using restriction enzymes
- Insulin coding gene joined with plasmid using different enzymes
- Modified plasmid re inserted to bacterial cell, which is now genetically modified
- Bacteria are cultured in fermenters
- Bacteria multiply
- Insulin secreted in to solution which bacteria are growing in, and is then extracted
122
What are restriction enzymes?
These are enzymes used to cut DNA in a way that the 2 strands of DNA removed from the chromosome will overlap. The longer strand, known as the sticky end will attach to the sticky end of another strand, through base pairing.
123
In what 2 scenarios is down streaming used?
- Insulin production
| - Penicillin manufacturing
124
Give 3 reasons why down streaming can be expensive and time consuming?
- Very small microbes/chemicals involved
- High tech equipment needed
- Skilled technicians/scientists needed
125
Give 3 advantages of genetically engineered insulin?
- Can produce human insulin
- No allergies or side effects
- Can be produced in larger quantities
126
What is a fertilised egg known as?
A zygote
127
Describe process after fertilisation? ( 4 steps )
- Zygote travels down oviduct and divides through mitosis, to form embryo
- Embryo implants in uterus wall. Thick wall holds and nourishes the embryo
- The embryo differentiates to produce variety of tissues and organs
- Embryo forms in to foetus
128
What is the function of the umbilical vein?
Carries substances from mother to foetus
129
What is the function of the umbilical artery?
Carries substances from foetus to mother
130
Give 3 ways placenta is adapted for diffusion?
Large surface area
Good blood supply
Thin membranes
131
Name 3 types of contraception?
- Mechanical
- Chemical
- Surgical
132
Give an example of mechanical contraception? Advantages and disadvantages?
- Condom
- Protects against STD's
- Unreliable if not used properly
133
Give an example of chemical contraception? Advantages and disadvantages?
- Contraceptive pill
- Very reliable
- Can have side effects eg. Weight gain
134
Give an example of surgical contraception? Advantages and disadvantages?
- Vasectomy
- Virtually 100% reliable
- Very difficult/impossible to reverse
