Yr 11 January Exams Flashcards
(156 cards)
0
Q
What is the structure of a plant cell?
A
- nucleus
- cell membrane
- cell wall
- vacuole
- chloroplasts
- cytoplasm
- nuclear membrane
1
Q
What is the structure of an animal cell?
A
- nucleus
- membrane
- cytoplasm
- nuclear membrane
2
Q
What is the equation for magnification?
A
Magnification = Observed Size
—————– OR Objective Lens X Eye lens
Actual Size
3
Q
Structure of Bacterial cells?
A
- loop of DNA
- plasmids
- cell membrane
- non cellulose cell wall
- cytoplasm
4
Q
Do Bacterial Cells contain chromosomes?
A
No
5
Q
Animals grow evenly throughout the body. Plants don’t, they grow in regions called….?
A
Apices
6
Q
What are stem cells?
A
Very simple and undifferentiated cells in found in young animal embryos
7
Q
How to get micro metres?
A
Mm divided by 1000
8
Q
What are the levels of organisation in organisms?
A
Cells - Tissues - Organs - Organ Systems - Organism
9
Q
What does selectively permeable mean?
A
Some substances can pass through but others can’t
10
Q
What does fully permeable mean?
A
All substances can pass through
11
Q
What is diffusion?
A
When molecules in a region of high concentration move to an area of low concentration
12
Q
Name the 3 factors which affect the rate of diffusion?
A
- size of molecules
- temperature of substance
- concentration gradient
13
Q
Why do you place the leaf in boiling water in a starch test to see if light is needed for photosynthesis?
A
To kill the leaf and stop chemical reactions
14
Q
Why do you boil the leaf in ethanol in the starch test to see if light is needed for photosynthesis?
A
To remove the green pigment, chlorophyll
15
Q
Where does photosynthesis occur in plant cells?
A
The chloroplasts
16
Q
Word equation for Photosynthesis?
A
Chlorophyll
CO2 + Water ———–> Glucose + Oxygen
Light
17
Q
How do carbon dioxide and oxygen enter and leave the leaf?
A
Carbon dioxide enters the stomata and diffuses in the small air spaces in to the palisade mesophyll layer. Photosynthesis occurs and oxygen leaves through the stomata through diffusion.
18
Q
Do stomata stay open all day and night?
A
No, the guard cells change shape and close the stoma during the night
19
Q
How is the leaf adapted for light absorption?
A
- short distance between bottom and top of leaf so all cells receive light
- large surface area
- transparent waxy cuticle
- palisade mesophyll is tightly packed with tall thin cells
20
Q
Word equation for respiration?
A
Glucose + Oxygen —-> CO2 + Water + Energy
21
Q
Name the 3 things the products of photosynthesis can be used for?
A
- respiration
- storage
- growth
22
Q
In some experiments to prove carbon dioxide is needed for photosynthesis, what chemical would they add in a flask with a leaf in it?
A
Sodium Hydroxide ( Soda Lime ) which removes CO2
23
Q
Higher light intensity _________? the rate of photosynthesis
A
Increases
24
Higher temperature decreases rate of photosynthesis. True or False?
False
25
Higher CO2 increases the rate of photosynthesis. True or False?
True
26
What is the compensation point?
Where both rates of respiration and photosynthesis are equal
27
When does the compensation point naturally occur?
Dusk and Dawn
28
Hydrogen Carbonate indicator is red. When CO2 levels increase, what colour does it turn?
Yellow
29
Hydrogen Carbonate is red. When CO2 levels decrease, what colour does it turn?
Purple
30
How to calculate energy in food?
Mass of water (g) X temp. rise (°C) X 4.2
Energy (J) = ---------------------------------------------
Mass of food sample (g)
31
How to calculate amount of Vit C in fruit juice sample?
Volume (ml) standard ascorbic acid solution X 1%
Vitamin C (g) = --------------------------------------------------------
Volume (ml) of fruit juice sample
32
What is BMI?
Body Mass Index ratio
Weight (kg)
-------------
Height in metres squared
33
What is your BMR?
Basal Metabolic Rate, a measure of minimum energy expenditure when someone is inactive.
34
How to calculate number of calories needed to maintain current weight?
BMR X Activity Levels
35
Name the 3 main functions of food?
- energy
- growth and repair
- protection
36
Name the 7 main nutrients?
- carbohydrates
- fats
- proteins
- fibre
- water
- vitamins C + D
- minerals
37
What elements are present in Carbohydrates, Fat and Fibre?
- Carbon
- hydrogen
- oxygen
38
What elements are present in protein?
- Carbon
- hydrogen
- oxygen
- nitrogen
39
1g protein gives?
1g fat gives?
1g fat gives?
- 17kJ
- 38kJ
- 17kJ
40
Energy requirements depend on what 3 factors?
- age
- gender
- activity levels
41
Name reagent for starch test?
Iodine
42
Name reagent for Benedict's Test?
Benedict's Solution
43
Name reagent for Buirets Test?
A mixture of copper sulphate and sodium hydroxide
44
What does Buirets test, test for?
Protein
45
Reagent for Emulsion test?
Ethanol
46
What does Emulsion test, test for?
Fat
47
Name reagent for DCPIP test?
DCPIP
48
What does DCPIP test, test for?
Vitamin C
49
What colour does iodine turn when starch is present?
From yellow/brown to Blue/black
50
What colour does Benedict's solution turn when sugar is present?
Blue to green to orange to Brick Red Precipitation
51
What colour does Buirets test reagent turn when protein is present?
Blue to Purple
52
What colour does ethanol turn when fat is present?
A white emulsion forms at top of solution
53
What colour does DCPIP turn when Vitamin C is present?
From blue to Pink to colourless
54
Name 6 health problems caused by poor diets?
- obesity
- heart disease
- stroke
- arthritis
- high blood pressure
- diabetes
55
What is digestion?
The breaking down of large insoluble molecules in to smaller soluble molecules
56
What is ingestion?
Taking food in to the alimentary canal through the mouth
57
What is absorption?
The passage of small soluble molecules along the wall of the intestine in to the blood stream
58
What is Assimilation?
Digested food molecules absorbed in to cells
59
What is egestion?
When undigested food passes out of the anus
60
What two types of digestion occur when food enters the mouth?
Physical and Chemical
61
How does chewing help digestion?
Breaks up food, increasing surface area for enzyme action
62
What is the function of saliva?
- It lubricates the food, making it easy to swallow
| - it contains amylase which breaks up insoluble starch molecules in to glucose
63
What is Peristalsis?
When muscles contract in a wave like movement forcing the food down to the stomach.
64
What is chyme?
When linings of the stomach have contracted rhythmically, churning the food in to a thick liquid called Chyme
65
Gastric Juice is produced in the linings of the stomach. What enzyme and acid does it contain?
- protease (pepsin)
| - Hydrochloric Acid which boosts the functioning of protease enzymes and kills any potentially dangerous micro organisms
66
What is the duodenum?
It is the beginning of the small intestine
67
What is the ileum?
The entire small intestine except for the beginning of it, the duodenum
68
What 3 solutions are secreted upon food in the duodenum?
- pancreatic juice
- intestinal juice
- bile
69
What enzymes does pancreatic juice contain?
- amylase
- protease
- lipase
- carbohydrase
70
Intestinal Juice has the same enzymes as Pancreatic Juice. True or False?
True
71
What are the 2 functions of bile in the duodenum?
- alkaline, neutralises acidic solution from stomach
| - it emulsifies large fat globules, in to small fat globules to increase surface area for lipase enzymes
72
What 3 enzymes are lastly secreted in the Ileum?
- protease
- amylase
- lipase
73
How do the small molecules of fat, glucose, amino acids, etc. get absorbed by the intestinal walls in the Ileum?
Diffusion
74
What are the 3 adaptions of the small intestine?
- large surface area
- good blood supply
- thin and permeable membranes
75
What enzyme breaks down the substrate Starch?
Amylase
76
What enzyme breaks down the substrate Protein?
Protease
77
What enzyme breaks down the substrate Lipids or Fat?
Lipase
78
What enzyme breaks down the substrate Carbohydrate?
Carbohydrase
79
What does Starch break down in to after a Catabolic reaction?
Glucose
80
What does Protein break down in to after a Catabolic Reaction?
Amino Acids
81
What do Lipids break down in to after a Catabolic Reaction?
Fatty Acids and Glycerol
82
What do Carbohydrates break down in to after a Catabolic Reaction?
Sugars
83
What are Enzymes?
Enzymes are proteins that act as Biological Catalysts that speed up biological reactions
84
What is the active site of an enzyme?
Where the enzyme reacts upon the substrate
85
What is the Lock and Key theory?
It proposes that any of enzymes active site is complementary to the shape of only one specific substrate, eg. Starch
86
What are Extra Cellular enzymes?
These enzymes leave the cell and do its job outside it
87
What are intra cellular enzymes?
These enzymes do their job inside the cell and do not leave it
88
What are the 4 factors that can effect enzyme speed or efficiency?
- Temperature
- Enzyme Concentration
- Substrate concentration
- pH
89
What is the Optimum pH/ Temp. of an enzyme?
This is the point where the enzyme will operate best at, but any higher or lower temp./ pH will decrease the efficiency of the enzyme
90
What is the optimum Enzyme Concentration/ Substrate Concentration of an enzyme?
This is the point where increasing the Enzyme/ Substrate concentration will have no effect on the speed at which the enzymes operate. Decreasing the concentration will decrease the speed though
91
What does the term Thermostable mean?
It can work over a wide range of temperatures
92
Name 1 commercial use of an enzyme?
Biological Washing powders
93
What is the function of the Intercostal Muscles?
They help the rib cage move while breathing
94
What is the function of the Pleural Fluid?
Reduces friction between lungs and ribs
95
What is the point of the nasal cavity?
To warm and moisten the air
96
What is the function of the rings of cartilage in the trachea and bronchi?
They support the trachea and bronchi and keep them open
97
What is the function of the alveoli?
Gas exchange
98
Name the 6 adaptations of the Alveoli?
- Large surface area
- Good blood supply
- Thin
- Moist
- Permeable
- Diffusion Gradient
99
ADAPTATIONS OF ALVEOLI
Why is having thin walls on the alveoli beneficial for gas exchange?
Provides a short diffusion distance
100
ADAPTATIONS OF ALVEOLI
Why is having a moist surface area around the alveoli beneficial for gas exchange?
The gases dissolve in the mixture, helping them diffuse through the alveoli walls and in to the capillaries
101
ADAPTATIONS OF THE ALVEOLI
Why is having a good blood supply beneficial for gas exchange?
Helps maintain the diffusion gradient of the two gases, oxygen and carbon dioxide
102
ADAPTATIONS OF THE ALVEOLI
Why is maintaining a diffusion gradient beneficial for gas exchange?
This encourages oxygen to diffuse in to the capillaries and carbon dioxide to diffuse in the alveoli
103
What colour does limewater turn when carbon dioxide is present?
Milky/ cloudy
104
What colour does Hydrogen Carbonate indicator turn when Carbon dioxide is added?
Red to yellow when added
| Red to purple when removed
105
What is the equation for Aerobic Respiration?
Glucose + Oxygen ----> Carbon Dioxide + Water + Energy
106
What is the Chemical Equation for Aerobic Respiration?
C6 H10 O6 + 6 O2 -----> 6 CO2 + 6 H2O + Energy
107
What is the equation for Anaerobic Respiration?
Glucose ----> Alcohol + Carbon Dioxide + Small amount of energy
108
What is the difference between Aerobic and Anaerobic Respiration?
Aerobic respiration includes the use of oxygen, but Anaerobic only uses Glucose to create a small amount of energy
109
Is water produced in Anaerobic Respiration?
No, alcohol is
110
What acid builds up in the muscles during Anaerobic Respiration?
Lactate ( Lactic Acid )
111
What 2 communication systems exist in the body?
The Nervous System and the Hormonal System
112
What does responding to the environment through the nervous system require?
A co-ordinator ( Brain or Spinal Cord)
113
What is the chain of reacting to the environment?
Stimulus ---> Receptor ----> Co ordinator ----> Effector ----> Response
114
What is the difference between a voluntary and involuntary response?
A voluntary response requires conscious thought, but an involuntary response doesn't require conscious thought
115
What three neurones are involved in a reflex action? Name them in order
- Sensory Neurone
- Association Neurone
- Motor Neurone
116
How neurones transmit between synapses?
The diffusion of transmitter chemicals
117
Name the three ways neurones are specialised for their function?
- Long
- Branched ends
- Have an insulating sheath
118
What is the function of the Conjunctiva?
It's a thin protective outer cover
119
What is the function of the Cornea?
Transparent part of eye that allows light to enter. Also slightly refracts light
120
What is the function of the iris?
Controls how much light enters the pupil
121
What is the function of the lens?
Refracts light in order to focus image
122
What is the function of the Ciliary muscle?
Changes the shape of the lens. Connected to lens by Suspensory Ligaments
123
What is the function of the Suspensory ligaments?
They change the shape of the lens, and connect the lens to the Ciliary Muscles
124
What is the function of the retina?
Light sensitive cells are found here, which detect image
125
What is the function of the optic nerve?
Contains neurones which send information to the brain
126
What is the function of the Aqueous Humour?
Watery fluid between cornea and lens. Keeps pressure right
127
What is the function of the Vitreous Humour?
Jelly like fluid between lens and retina. Keeps the eye's spherical shape
128
Describe light rays coming from a distant and a near object?
```
Distant = Parallel
Near = Diverging
```
129
Describe Ciliary Muscles with a distant object and a near object?
```
Distant = Relax
Near = Contract
```
130
Describe Suspensory ligaments with distant object and near object?
```
Distant = pull on lens
Near = Slack
```
131
Describe lens shape with a distant object and a near object?
```
Distant = Thin
Near = Thick
```
132
Why does a pupil dilate and constrict depending on light intensity?
Too little or too much light prevents image being produced
133
What two muscles are in the iris?
The Circular and the Radial Muscles
134
Describe Circular muscles in iris with bright light and dim light?
```
Bright = Contract
Dim = Relax
```
135
Describe Radial muscles in iris with bright light and dim light?
```
Bright = Relax
Dim = Contract
```
136
What is the pupillary reflex?
An automatic reaction which changes the size of the pupil
137
What are Hormones?
Chemicals produced by special glands that are released in to the blood
138
Are hormones a slow or fast reaction?
Slow
139
What hormone prevents blood glucose levels going too high?
Insulin
140
Where is insulin produced?
Pancreas
141
What 2 things does insulin do to reduce Blood Glucose levels?
- Converts glucose in to glycogen, which is stored in the liver
- Increase respiration in the liver
142
What hormone, produced in the pancreas, is produced when blood glucose levels are falling?
Glucagon
143
What does Glucagon do to increase blood glucose levels?
Converts Glycogen in to Glucose
144
What is the Negative Feedback System?
When the two hormones, Insulin and Glucagon are produced according to blood glucose levels, so as to keep the glucose levels at a normal level
145
What is Diabetes?
This is when someone can't produce Insulin
146
What 4 symptoms do Diabetics experience?
- High blood glucose levels
- Glucose present in urine
- Often thirsty
- Lethargy
147
What is a Hypoglycaemic attack?
A symptom that occurs when blood glucose levels drop too far
148
Name 4 long term complications for people who have had Diabetes for a long time?
- Eye damage
- Heart disease
- Strokes
- Kidney Damage
149
What is Phototropism?
When a plant bends towards light
150
What are the benefits of Phototropism?
More Light, More Photosynthesis, More Growth
151
What part of the plant is sensitive to light, and detects which way to bend?
The tip of the plant
152
When the plant bends, what is causing the to happen? What Hormone is responsible?
Cell elongation, caused by the hormone Auxin
153
What is the proper term for the type of growth the plant is carrying out during Phototropism and Cell elongation?
Differential Growth
154
Name the 4 commercial uses of plant hormones?
- Weedkillers
- Flower and fruit formation
- Rooting Powder
- Tissue Culture
155
Name the adaptations of the Villi in the Ileum?
- Large Surface Area for absorption
- Good Blood Supply ( Maintains diffusion gradient )
- Thin permeable membranes ( easier/ short diffusion distance)
- Lacteal able to absorb fatty acids and glycerol
