biology (y9) Flashcards
1
Q
function of ribosomes
A
make proteins
2
Q
what happens in mitochondia
A
respiration, releasing energy
3
Q
what does the nucleus of a cell do
A
controls activity of cell
4
Q
what does the cell membrane do
A
controls movement of substacnes in and out
5
Q
how do meristems help a plant develop
A
allow plant to grow longer roots, plant grows taller and wider
6
Q
what is a eukaryotic cell
A
a nomral cell: animal, plant, fungi etc, are normally arund 10-100 micrometers in size
7
Q
what is a prokaryotic cell
A
a simple organism, eg: bacteria, less than 2 micrometres in size
8
Q
what are the 4 phases of mitosis
A
prophase, metaphas, anaphase and telephase
9
Q
what happens in the prophase phase
A
chromosomes are 2 sister chromatids and a centromere. Nucleur enevelope breaks down, centriole from that divides into 2 and moves to opposite poles, spindles start to form
10
Q
what happens in the metaphase phase
A
chromosomes line up of equator of cell, attaches to spindle fibres
11
Q
what happens in the anaphase phase
A
centromere joining sister chromatids splits, fibres pull chromatids to opposite poles
12
Q
what happens in the telephase phase
A
nucleus develops around 2 ets of duplicated chromosomes, after mitosis occurs, cytokinese occurs when the cell splits into two parts
13
Q
what are meristems
A
groups of undifferentiated cells that dibide to make all the different cells of a plant
14
Q
what does phloem transport
A
sugars
15
Q
what does xylem transport?
A
water and minerals
16
Q
structure of phloem
A
elongated with pores
17
Q
structure of xylem
A
dead and hollow tubes
18
Q
where are xylem and phloem found in the leaf
A
in vascualr bundles- phloem near lower surface and xylem above it
19
Q
where are xylem and phloem found in the stem
A
near edge of stem, phloem closer to edge, xylem more inside
20
Q
where are xylem and phloem found in the root
A
centre of root, xylem in an ‘x’ with phloem tubes around it
21
Q
how are lungs and gills adapted for gas exchange
A
large SA, fast diffusion, good blood supply, thin walls, mainatins conc. gradient
22
Q
whta happens to intercostal muscles and diaphragm when we breathe in
A
intercostal muscles contract and move ribs up and awya, and diaphragm contracts and moves down lower to spine
23
Q
what is starch tested by and what is the original colour
A
iodine - orangey, brown
24
Q
what is protein tested by and what is the original colour
A
biuret solution, light blue
25
what is lipid tested by and what is the original colour
ethanol - clear
26
what is glucose tested by and what is the original colour
benedicts solution - blue
27
what colour would a substance turn if it had starch in it
blue black
28
what colour would a substance turn if it had glucose in it
tomato red
29
what colour would a substance turn if it had lipid in it
milky white
30
what colour would a substance turn if it had protein in it
pale purple
31
what type of food is digested in the stomach and by what enzyme
protein, by protease
32
what is transpiration : two answers-
the evaporation of water vapour from the stomata of a leaf, the movement of water from the leaves to the plant to the leaves
33
4 sections of the leaf
upper epidermis, palisade mesophyll, spongy mesophyll, lower epidermis
34
4 ways transpiration is affected
light- more bright light increases it, temperatue- higher temperature means quicker evaporation and diffusion, wind- water vapour is removed quickly by air movment, humidity- is slower because extra vapour in the air
35
what is the movement of sugars called
translocation
36
5 uses of glucose:
respiration, energy - storage of it, plant growth and repair and strengthening plant cell walls
37
what are absorbed by active transport in the roots ( from the soil)
nitrate ions
38
how are leaves adapated to maximise photosynthesis
large SA - more space to absorb sunlight,
chlorophyll - absorbs sunlight makes sunlight into energy and chemicals, have stomata - to allow c02 and 02 to diffuse in and out ,
network of veins - to support leaf and transport water and carbs,
wax cuticle - lets light out and protects sufrace of leaf.
39
word euqation for photosynthesis
water + carbon dioxide = (by light) =glucose + oxygen
40
symbol equation for photosynthesis
6C02 +6H20 goes to C6H1206+602
41
what does cell sap do?
stores chemicals and helps control water content of cell
42
what does a chloroplast do?
absorbs light for photosynthesis
43
what does a vacuole do?
maintains cell shape and stores cell sap
44
what does the cell wall do?
support cell and keep its shape
45
where are meristmes usually found?
in shoots tops and stems of plants
46
once stem cells are removed from a ? - ?day old embryo it can turn into any ? of cell
3-5, type
47
what are specialized cells?
cells that have structures - adaptations that allow them to do a particular job
48
eukaryotic cell vs prokaryotic cell : a EK has a nucleus, ? , normally a cell ?, has membrane bound organelles, a flagellum (?), and ribosomes , whereas a PK cell has DNA, it always has a cell? , has ribosomes, is a capsule and ? has a flagellum
DNA, wall, sometimes, wall, mostly
49
what 4 parts do animal cells not have that plant cells do?
cell wall, cell sap, chloroplasts and a permanent vacuole
50
cons of stem cells!
1. embryos don’t have to be used, can use ? cells instead
2. body can sometimes ? stem cells
3. people may have different opinions, eg : if they are religious - ?, or if they had personal experiences- like a ?
adult, reject, Christianity, miscarriage
51
what conditions can be cured by stem cells?
Parkinson’s, diabtetes, arthritis
52
stem cells are in specialized cells that can ? each other to make identical ? cells which can then make many different types of ? cells
copy, stem, specialized
53
cons of adult stem cells?
can’t make as many different types of specialized cells
54
where are stem cells found?
bone marrow, embryos, and shoot tips (meristems)
55
how many pairs of chromosomes in humans?
23 pairs
56
chromosomes are found in the nucleus, what substance us arranged into chromosomes ?
DNA
57
mitosis functions in multicellular organisms :
growth and repair of tissues as well as asexual reproduction
58
functions of mitosis in unicellular organisms:
binary fission
59
how is a root hair cell specialized?
has a thin cell wall, large SA, and many mitochondria for respiration
60
how is a red blood cell specialized?
is biconcave, has no nucleus so it can fit max amount of haemoglobin
61
how is a nerve cell specialized?
they are long and thin and form connections with neurones and muscle cells
62
how is a cone/rod specialized?
they have many mitochondria, and the outer segment is filled with visual pigment
63
how is a fat cell specialized?
has a (large) energy store, very little cytoplasm and can increase in size
64
how is a muscle cell specialized?
is elongated, can contract and has lots of mitochondria
65
order cell, organism, organ system, tissue and organ in order from largest to smallest :
organism —> organ system —> organ —> tissue —> cell
66
what happens when you breathe out?
the intercostal muscles relax, ribs move down and closer to spine, and the diaphragm relaxes and moves up and the vol of air in chest decreases
67
what is the definition of diffusion?
the spreading of the particles of a gas, eg : oxygen or particles im of any solution eg : glucose, resulting in a movement of particles from an area of high conc to an area of low concentration.
68
what factors affect and increase diffusion time?
Hugh remix large SA, higher gradient and smaller particles eg: lots of particles to a few
69
what state has the fastest diffusion?
gas
70
due to a smaller SA : ? ratio in multicellular ?, surfaces and organ systems need to be ? to exchange materials effectively
Vol, organisms, specialised
71
effectiveness of an exchange system is increased by 4 different factors - name them and describe how it improves diffusion :
large SA - more space for diffusion,
thin membrane (normally one cell thick) - a short diffusion path,
good blood supply - steep conc gradient,
well ventilated - also steep concentration gradient.
all of these mean a faster rate of diffusion
72
what is active transport?
moving up or against a concentration gradient, or when molecules/ions move against a conc gradient across a semi permeable membrane
73
what does active transport use energy for? (and where does the energy come from?)))
to make ‘protein pumps’ which move particles the wrong way - this energy is from aerobic respiration so could be for example glucose from intestine into blood
74
which route does O2 take to get to the blood? and how is the route for CO2 different?
O2 passes through trachea —> bronchus —> bronchiole —> alveoli —> blood, CO2 is different as it goes the opposite way and leaves the blood and body
75
what is osmosis?
when water moves from an area of high conc of water to an area of low concentration of water across a semi-permeable membrane!!! x
76
what is the difference between high and low conc and high and low water conc
high conc is the same as low water conc and vice versa with low conc and high water conc
77
what would happen to a cell that had been put in 1.0 M of sucrose? (OSMOSIS)
the cell would contain less water as the water would diffuse across the semi permeable membrane due to the high conc of water in the cell and low conc of water in the sucrose. this leads to it losing water and becoming FLACCID
78
what would happen to a cell that had been put in 0.0 M of sucrose? (OSMOSIS)
it would get full of water as it would absorb all the water since the water is moving from a low conc to a high conc (or high water conc to low water conc) and because of this it’ll be quite hard and turgid
79
potato chip experiment - need to be able to explain osmosis… what happened to the mass of the 0.0M chip and the 1.0M chip - COMPARE!!!
mass increased for 0.0M, while 1.0M stayed the same and even slightly lost mass
80
what is a hypotonic solution?
hypo - so lower, so low conc, so a solution with a high concentration of water and therefore a dilute solution
81
what is a hypertonic solution?
hyper means higher, so high conc, low water concentration, so concentrated solution!
82
what’s an isotonic solution?
a normal solution
83
what happens to red blood cells if put in a hypotonic solution?
they burst as they absorb so much water - cause low to high - water diffuses across the semi permeable membrane into the rbc s !
84
what happens to red blood cells if put in a hypertonic solution?
they become crenated/crinkled as there is a high conc outside and low inside so water will diffuse out across the semi permeable membrane
85
where are meridtems found?
tips of roots and shoots, and around vascular tissue in stems
86
what types of plants can easily be cloned with meristems?
plants that are resistant to diseases!
87
what are xylem and phloem called together?
transpiration stream
88
what do roots stems and leaves work together to do?
transport water, sugar and minerals around cells
89
leaf - a site of gas exchange and ? , and water loss by ?
stem - supports plant, transpiration ?
roots - anchor plant and absorb ? and dissolved ?
photosynthesis, transpiration, stream , waterrr, materials!
90
what is the acronym for uses of glucose?
RSPCA - respiration, starch, protein, cellulose and fats
91
what can magnesium deficiency cause?
yellow leaves
92
what can a nitrate deficiency cause?
poor growth, yellow leaves
93
what can potassium and phosphorus deficiency cause?
both - discoloured leaves
potassium - poor growth of fruit
phosphorus - poor root growth
94
what is the independent variable plotted on and why?
the x axis, as it is the factor you are changing
95
what axis is the dependent variable plotted on and why?
the y axis, as it is the one you are measuring and it is dependent on the independent variable - like a metal rod or a stand is dependent on the balancing part of the stand
96
parts of the upper epidermis (and characteristics)
section closest a to surface, has no chloroplasts (sun shines through to palisade mesophyll for photosynthesis) , has a waxy cuticle which stops water evaporating from leaves
97
palisade mesophyll?
where 80% of photosynthesis happens, near top for max photosynthesis, palisade cells are packed tightly to maximise no of cells and photosynthesis as well as chloroplasts being at the top of cells for max sunlight!!!
98
spongy mesophyll
where most gas exchange happens, has a large SA for co2 absorption from irregular shaped cells - (have chloroplasts so can photosynthesise), has air spaces for co2 to move to palisade later for photosynthesis, as well as stores vascular bundle of xylem and phloem (transport sugar, water and minerals as well as products of photosynthesis , eg: o2 )
99
lower epidermis
lots of stomata for gas exchange, bring in co2 for photosynthesis (and take out o2) , stomata are controlled by guard cells which open and close for o2 and co2 diffusion in and out
100
when does the stoma/stomata open?
when guard cells fill with ? by osmosis,
the thicker inner ? stretches less than the thin ?wall,
making the guard ? bend in a banana shape,
the stoma then ? between the guard cells
water, wall, outer, cell, opened
101
translocation - what happens?
sugars are transported from ? for immediate use for respiration, normally these are as sucrose and as ? acids, this is by the use of ? cells, and is an active process meaning it can move in ? direction but ? at the same time
leaves, amino, phloem, any, NOT
102
equation for intensity?
1/d squared
103
in a graph of rate photosynthesis plotted against temp, why is the rate so low at 5 degrees and at 80?
at 5 degrees it is just the start of the experiment and the rate is rising but the enzyme hasn’t got to its optimum temperature yet (37 degrees so room temp) , however at 80 it has gone past the optimum temperature meaning that it is too hot for rhe enzyme to function and it starts to denature it - meaning the enzyme gradually loses its use and by 80 degrees it is fully denatured and cannot function anymore
104
what does a potometer measure?
the rate of transpiration by uptake of water
105
how does a potometer work?
you measure the time and how far the air bubble has gone in that time and then work out the rate by how many cm per minute the bubble has moved
106
transpiration process : water from soil enters ?, via root hair ? water then moves from cell to ? till it meets the ? , where xylem and ? transport water around the rest of a plant - eg : going into a leaf and giving water to the ? in the leaf to hydrate the leaf
roots, cell, cell stem, phloem, xylem
107
what does a watering system do?
delivers a regular supply of water
108
what does hydroponics do?
it is a controlled watering system that grows roots in rock wool and mineral rich water
109
what does shading help control?
amount of light and temp
110
what is biological control?
a relatively closed growing environment that can use organisms to control pests
111
what does ventilation help control?
temp and humidity
112
humidifiers reduce what?
transpiration and need for watering since they add more moisture to the air
113
what does heater a do?
increases temp so more photosynthesis
114
what does heater b do?
increase conc of co2 if a paraffin heater is used, and high concentration of CO2 means high rate of photosynthesis
115
there will always be starch when you have both light and ?
CO2
116
what colour is a non variegated leaf?
green
117
where does the breakdown of starch take place?
mouth, small intestine
118
where is amylase made?
duodenum (small intestine), pancreas and salivary gland
119
where are amino acids digested?
in the stomach and small intestine
120
where’s fat digested? (and what is it digested into and by)
small intestine, into fatty acids and glycerol and by lipase
121
how does bile and lipase emulsify fat?
lipase work over the surface of the ? , then the bile emulsified the ? into tiny droplets of ? which lipase then works over the surface of each of these ? and emulsified them into fatty acids and ?
drop (of fat), drop, lipid, droplets, glycerol
122
how does increasing the SA Of lipids aid digestion ?
because they are easier to digest as they can be absorbed easily by villi
123
how are leaves adapted to maximize photosynthesis?
large SA, chlorophyll, stomata, network and veins, wax cuticle
124
where are sugars made?
in the companion cell!
125
where do sugars diffuse into phloem from?
companion cell
126
what happens when water enters phloem by osmosis?
movement of water in phloem makes sugars sunk to the root
127
what happens when sugars have sunk from the phloem to the sink cell/root
sucrose is stored as starch
128
what is bile?
ab alkaline liquid which neutralizes stomach acid and provides optimum pH for pancreatic enzymes
129
what enzymes are only made in the pancreas?
proteas and lipase
130
movement of water in root hair cells :
1. root hair cells have a large ? for water ?
2. water enters root hairs by ?
3. water moves across root 1 ? at a time
4. water renters xylem of ?
5. water moves up xylem in ? and then leaves xylem and enters ? cells by osmosis
6. water moves across leaf ? cell at a time
7. remaining water ? into the air spaces of spongy ?
8. this raises the humidity, so from air ? water diffuses out of ? and evaporates from surface of ?
SA, uptake/absorption,
osmosis,
cell,
stem,
stem, leaf,
1,
evaporates, mesophyll,
spaces, stomata, leaf
131
what is fat used for?
to make cell membranes and cholesterol and vitamins
132
Main steps to testing a leaf for starch
1. Observe and draw variegated leaf beforehand
2. Fill a beaker with lots of hot water from a kettle and then put leaf in
3. Leave leaf for 1 minute (make it less waterproof and soft)
4. Take out leaf, put it in a boiling tube and cover in ethanol
5. Put tube into a beaker of hot water. Ethanol should boil (as it has a bpt of 78 degrees)
6. Pour ethanol away and dip leaf back into water beaker to remove ethanol
7. Spread leaf on a while tile and add about 5 drops of iodine. Wait 2 minutes
8. Draw leaf again and label the change you see
133
Variegated leaf before and after testing
- white for non starch/ chlorophyll and green for containing chlorophyll
- orange for non starch, blue black for containing chlorophyll and green
