the whole syllabus Flashcards
(84 cards)
1
Q
all typical cells have
A
Cell membrane: differentially or partially permeable to
allow certain substances to enter and leave the cell.
Cytoplasm: where chemical reactions take place
Nucleus
Mitochondria: organelle where aerobic respiration
happens
Ribosome: makes protein and can be found floating
within the cytoplasm
2
Q
only plant cells have
A
Vacuole: stores food & water & helps to maintain
shape of cell
Cell wall: rigid to keep shape of cell
Chloroplasts: contain chlorophyll, which absorbs light
energy for photosynthesis
3
Q
Cillated cells - characteristics
A
Move and push
mucus
Tiny hairs called
cilia
4
Q
Xylem vessel characteristics
A
Transport water and support plant
No cytoplasm so water passes freely
No cross walls so cells connect (cohesion) to form tube
Lignin makes it strong and waterproof
5
Q
Palasite cells characteristics
A
Photo-synthesizes
Regular shape so many can fit in a small space
Many chloroplasts
6
Q
muscle cells characteritics
A
Contracts to get structures closer together
Long
Many protein fibres in cytoplasm to
shorten cell when energy available
7
Q
magnification formula
A
image / actual
8
Q
virus and bacteria cells
A
virus: non living unless in host, protein coat, only a few DNA genes
bacteria: living, cell wall, many DNA genes
9
Q
Monocotyledons and Dicotyledons
A
Monocotyledons. Dicotyledons
One cotyledon Two cotyledons
Parallel veins Veins netlike
Floral parts in 3s. Floral parts in 4s or 5s
10
Q
Diffusion
A
movement of molecules from a region of high
concentration to a region of low concentration down the
concentration gradient.
ex: The smell of perfumes/Incense Sticks.
11
Q
Osmosis
A
Movement of water molecules from a region of high-
water potential to a region of low water potential, through
a partially permeable membrane
12
Q
Active Transport
A
Movement of particles through a cell membrane, from a
region of lower concentration to a region of higher
concentration against a concentration gradient, using
energy released during respiration
Active transport is needed when an organism wants to
optimize the amount of nutrients it can take up
13
Q
test for starch
A
iodine solution
orange to blue
14
Q
test for glucose/reducing sugars
A
benedict’s solution
blue to orange
15
Q
test for protein
A
biuret solution
blue to violet
16
Q
test for lipids
A
ethanol
cloudy emulsion forms
17
Q
Enzyme and Catlayst definition
A
Catalyst: a substance that speeds up a chemical reaction
and is not changed by the reaction
Enzymes: proteins that function as biological catalysts
18
Q
how enzymes work and uses
A
the enzyme and complementary shape collide, enzyme-substrate complex forms, reaction occurs, products are released from active site
uses: biological washing powder, food industry (Pectinase helps break down cell walls in fruit juice
production) , seeds to germinate…
19
Q
enzyme: amylase
substrate?
endproduct?
A
enzyme: amylase
substrate: starch
endproduct: maltose
pancreas and salivary glands
20
Q
enzyme: lipase
substrate?
endproduct?
A
enzyme: lipase
substrate: lipids
endproduct: fatty acids and glycerol
pancreas
21
Q
enzyme: maltase
substrate?
endproduct?
A
enzyme: maltase
substrate: maltose
endproduct: glucose
22
Q
enzyme: protase
substrate?
endproduct?
A
enzyme: protase
substrate: protein
endproduct: amino acids
Pepsin comes from the stomach and trypsin comes from the pancreas.
23
Q
Photosynthesis definition and formula
A
process by which plants manufacture
carbohydrates from raw materials using energy from
light.
CO2 +H2O –> Glucose + O2
–> = light and chlorophyll
24
Q
for what do plants use glucose
A
as a source of energy for respiration storage, convert it into starch energy source in seeds (lipids) to make cell walls (cellulose) to make proteins (amino acids)
25
leaf structure
Cuticle
Epidermis: transparent cell that allows sunlight to pass
through to the palisade cell
Palisade: found at the top of the cell and contains many
chloroplasts which absorbs sunlight.
Spongy mesophyll layer: create air spaces to allow gaseous exchange to take place
Vascular Bundle: made up of xylem and phloem
Stomata: little holes that opens and closes to allow
gaseous exchange to take place. The stomata close to
prevent water loss and open to let gases come in and out.
26
Xylem and Phloem
Functions of xylem and phloem:
To transport substances from source, where they are
taken in or made, to the sinks, where they are used
To support the stem
Xylem: vessel which transports water and dissolved
minerals and has lignified walls made of cellulose, Water moves up due to transpiration and osmosis
Phloem: transports sucrose and amino acids up and down the plant. This is called translocation
27
mineral requirements of plants
nitrogen - protein synthesis
| magnesium - chlorophyll synthesis
28
uses of human nutrition
```
carbohydrates - energy
protein - growth and repair
lipid - insulation and energy storage
fibre - provides roughage
vitamin C - prevents cells from ageing
vitamin D - absorbtion of calcium
calcium - Development and maintenance of
strong bones and teeth
Iron - Making haemoglobin
Water - for Chemical reactions, solvent for
transport
```
29
```
human alimentary canal
stomach
pancreas
liver
gall bladder
large intestine
small intestine
```
stomach - protase enymes chemically digest proteins, hydraolic acid kills bacteria in food and provides optimum pH for enzymes
pancreas - produces all digestive enzymes
liver - produces bile (its role is to emulsify fats, to increase surface area for the action of enzymes.), stores glucose as glycogen
gall bladder - stores bile from liver
large intestine - Colon: organ for absorption of minerals and vitamins, and reabsorbing water from waste to maintain body’s water levels; and rectum
small intestine: the region where digested food is absorbed
Duodenum and Illeum (This is where absorption takes place; adapted by having
villi and microvilli.)
30
Structure of a Tooth
Pulp cavity, Enamel, Dentine, Cement, Nerves, gum, blood capilaries
31
absorbtion (small intestine) elements
Capillary: transports glucose and amino acids
Vein: delivers absorbed products to liver
Gland: produces enzymes
Lacteal: absorbs fatty acid and glycerol
Epithelium: only one cell thick for faster transport. The
cells of the epithelium are folded to form microvilli.
32
Pathway of Blood through the Heart
Deoxygenated blood coming from the body flows into the right atrium via the vena cava
the heart gives a little beat and the blood is pushed through the tricuspid valve into the right ventricle
the blood is pushed into the pulmonary artery
The blood travels to the lungs
Oxygen-rich blood returns to the left atrium via the pulmonary vein
It passes through the bicuspid valve into the left ventricle
The thicker muscle walls of the left ventricle contract strongly to push the blood forcefully into the aorta and all the way around the body
33
aorta, atrium and ventricle, vena cava
Aorta: carries oxygenated blood from left ventricle to rest
of body
Right atrium: collect deoxygenated blood & pump it to
right ventricle
Right ventricle: pumps deoxygenated blood to lungs
vena cava: Deoxygenated blood coming from the body flows into the right atrium via the vena cava
34
vessel: Artery definition and structure
AWAY
Transport high pressure blood away from heart
```
Elastic walls expand and relax as blood is forced out
Thick walls withstand
high pressure
Rings of muscle narrow
or widen artery to control
blood flow.
```
35
vessel: capillary definition and structure
Allow substances to diffuse into cells
One cell thick wall for
easy diffusion
36
vessel: vein definition and structure
Transport low pressure blood to the heart
Valves prevent backflow
of blood.
37
what is in blood
Red blood cells: haemoglobin and oxygen transport
White blood cells: phagocytosis and antibody formation
Platelets: causing clotting
Plasma: transport of blood cells, ions, soluble nutrients,
hormones, carbon dioxide, urea and plasma proteins
38
lymphocytes (white blood cells)
active and passive immunity
Large nucleus, they
produce antibodies to destroy pathogenic cells
active immunity - defence against a pathogen by antibodies
passive is short term defence aquiref from another (mother to child through breast feeding)
39
phagocytes
engulf pathogen, release digestive enzyme to digest pathogenic cells
40
function of cillia and mucus
traps bacteria and dust parcticles, cillia beat and push the mucus away from the throat, mucus produced by goblet cells
41
breathing in/ brathing out
```
breathing in:
external intercostal muscloes contract
ribcage moves up and out
diaphragm contracts and flattens
volume of thorax increases and the pressure decreases
air is drawn in
```
42
```
inhaled and exhaled air
inhaled:
O2: 21%
CO2: 0.04%
Nitrogen: 78%
water vapour:
```
```
exhaled
O2: 16%
CO2: 4%
N: 78%
water vapour: higher
```
43
Uses of energy in the body of humans:
muscle
contraction, protein synthesis, cell division, active
transport, growth, the passage of nerve impulses and the
maintenance of a constant body temperature.
44
Anaerobic Respiration
Release of a relatively small amount of energy by the
breakdown of food substances in the absence of oxygen.
produces lactic acid which is removed w combining O2, removing is needed to lower pH
in muscle:
Glucose → Lactic Acid
in yeast:
Glucose → Ethanol + Carbon Dioxide
45
Function of Kidney
regulate water content in body, exrete toxic waste products of metabolism (urea) and substances in excess (salts)
46
Renal artery, Renal vein, Ureter
Renal artery: brings wastes and water from blood
Renal vein: reabsorbs water and useful molecules and
leaves wastes behind
Ureter: carries urine from kidney to bladder
47
nerve impulse definition
electrical signal that passes along nerve cells called neurones, consists of central nervous system(the brain and spinal cord) and peripheral nervous system(all nerves)
48
Involuntary and Voluntary response
involuntary response - automatic, fast, protective, does not involve the brain as coordinator of action
49
3 types of neurones
relay - (connector) found inside the CNS and connect sensory and motor neurones
part of PNS:
sensory - carries diff impulese from sense organs to the CNS
motor (effector) - carry impulses from the CNS to effectors (muscles or glands)
50
reflex pathway
stimulus - receptor - sensory neurone - relay neurone - motor neurone - effector - response
51
Synapse
Synapse: a junction between two neurones, consisting of a gap across which impulses pass by diffusion of a
neurotransmitter
52
```
eye
Cornea:
Iris:
Lens:
Retina:
Optic nerve:
```
Cornea: refracts light
Iris: controls how much light enters pupil
Lens: focuses light onto retina
Retina: contains light receptors most in in the fovea, cones for colors and rods for detail
Optic nerve: carries impulses to the brain
53
pupil reflex, adjusting for high and low light intensity
Low Light Intensity
Radial muscles contract making it wider, to let more
light enter, to form a clear
image on retina
```
High Light Intensity
Circular muscles (circular lines) contract reduce the size of the pupil
```
54
hormone
A chemical substance, produced by a gland, carried by the blood, which alters the activity of one or more specific target organs
55
```
function? gland?
Hormone:
andrenaline
insulin
testosetrone
oestrogen
```
andrenaline - andrenal gland - Prepares body for vigorous action
insulin - pancreas - Reduces conc. of glucose in blood
testosetrone - testis - Causes development of male
sexual characteristics
oestrogen - ovary - Causes development of female
sexual characteristics
56
Homeostasis
| example: decrease in body temp
Homeostasis is the maintenance of a constant internal environment
decrease in body temp:
thermoceptors detect change
shivering, skin hairs erect (acts as insulator, less heat lost by radiation)
increase in body temp
Vasoconstriction: arterioles, which supply
blood to the skin-surface capillaries, constrict
to allow less blood near to skin surface to
decrease heat loss
57
antibiotics
dont work on viruses because they disrupt cell functions or break down cell structure, viruses dont have these
58
Sexual reproduction and Fertilisation deff
Sexual reproduction: process involving the fusion of the
nuclei of two gametes (sex cells) to form a zygote and the
production of offspring that are genetically different from
each other
Fertilisation: the fusion of gamete nuclei
59
flower parts
Sepal: protect the flower bud.
Anther: has pollen sacs with pollen grains which contain
the male nucleus (male gamete).
Stigma: platform on which pollen grains land
Ovary: hollow chamber, ovules grow from the walls.
60
Female reproductive system:
Ovary: contains follicles which develop into the ovary and
produces progesterone and oestrogen
fallopian tube: carries the egg cell to uterus
Uterus: where the fetus develops.
Cervix: neck of uterus: a strong rigid muscle, moist by
mucus with a small opening
61
FSH and LH
progesterone and oestrogen
produced in piturary gland
FSH stimulates development of eggs, causes oestrogen to excrete
LH stimulates ovulation, causes secretion of progesterone
oestrogen stimulates growth of the lining of the uterus
Progesterone maintains the uterus lining
62
oestrogen and progesterone
oestrogen - stiulates the uters to develop a lining, post ovulation, onhibits FSH and LH production
progesterone - maintains and thickens lining, inhibits prod of LH and FSH , levels drop if menstruation occurs
63
fertilisation steps
1) sperm touches egg membrane
2) enzymes break down jelly coat
3) protein on sperm cell bing with egg receptors
4) sperm nucleus enters egg cytoplasm
5) cell membrane becomes impermeable
6) zygote divides over and over and makes an embryo that implants in uterus
64
How HIV affects the immune system:
Infects and destroys lymphocytes
Decreases efficiency of immune system
Body becomes liable to infection by other pathogens
65
Inheritance definition
The transmission of genetic information from
| generation to generation
66
Chromosome definition
a thread-like structure of DNA, made up of
| a string of genes
67
Gene definition
a length of DNA that
codes for a specific protein. A gene may be copied and
passed on to the next generation
68
DNA
DNA controls cell function by controlling the production of proteins (some of which are enzymes), antibodies and receptors for neurotransmitters
69
Protein synthesis - transcription and translocation
- the gene coding for the protein emains in the nucleus
- mRNA molecules cary a copy of the gene (base sequence) to the cytoplasm
- the mRNA passes through ribsomes, who 'read' the code on the mRNA in groups of three
- the ribsome translates the sequence of the bases into a sequence of aminoacides that make up protein
- once the amino acid chain has been assembled it released form the ribseome so it cand form the final structre of the protein
70
mitosis
| def, role, process
definition:
nuclear division giving rise to genetically identical cells
role:
growth, repair of damaged tissues, replacement of cells and asexual reproduction
process:
exact duplication of chromosomes occurs before mitosis, at the end of the mitotic cell division, no of cells is doubled and the daughter cells produced are identical to parent
produced - 2 daughter cells
stem cells - unspecialised cells that divide by mitosis to produce daughter cells that can be specialised for specific functions
71
meiosis
| def
def:
nuclear division giving rise to cells that are genetically different, it is involved in the production of gametes, Reduction division in which the chromosome number is
halved from diploid to haploid resulting in enetically different cells
produced - 4 daughter cells
72
Genotype and Phenotype
```
Genotype: genetic makeup of an organism in terms of the
alleles present (e.g. Tt or GG)
Phenotype: physical or other features of an organism due
to both its genotype and its environment (e.g. tall plant or
green seed)
```
73
Homozygous and Heterozygous
Homozygous: having two identical alleles of a particular
gene (e.g. TT or gg). Two identical homozygous individuals
that breed together will be pure-breeding
Heterozygous: having two different alleles of a particular
gene (e.g. Tt or Gg), not pure-breeding
74
Sex-linked characteristic definiton
a characteristic in which the gene responsible is located on a sex chromosome and that this makes it more common in one sex than in the other
75
continuous and discontinuous variation
Continuous variation - results in a range of phenotypes between two extremes, e.g. height in humans
Discontinuous variation - results in a limited number of distinct phenotype, caused by genes (e.g. you are either blood group O, A, B or AB, nothing else)
76
evolution
change in adaptive features over time as a result of natural selection
eg: antibiotic resistance
77
features on egg and sperm cell
sperm:
flagellum - motility
acrosome - enzymes to get past the egg's coat
nucleus - contains DNA
egg:
cytoplasm - nutrients for early embryo
cell membrane - changes qafter fertilisation so that no sperm can enter
mitochondria - energy
78
draw carbon cycle
see picture
79
nitrogen cycle
| Nitrogen fixation, Nitrification, Denitrification
nitrogen fixation - Nitrogen-fixing bacteria provide usable nitrogen for plants, these may exist in the root nodules, or this can happen because of lightning
Nitrification - Nitrifyng bacteria -
convert nitrogen-containing substances (deamination, decomposition of plant and animal protein) into better nitrogen-containing substances for the plants.(nitrate ions)
Denitrification - Denitrifying bacteria: they convert
nitrogen-containing substances into atmospheric nitrogen
80
etapele curului meu
Lag phase: number of mature, reproducing individuals is
low and they may be widely dispersed
Log phase: exponential growth occurs, the conditions are
ideal and maximum growth rate is reached
Stationary phase: when mortality rate = birth rate
81
Why are microorganisms used in biotechnology
Bacteria and fungi are small and easy to grow in a lab
They reproduce quickly and don’t take up much space
No ethical issues involved
Genetic code is the same for bacteria as it is for
human
Bacteria have loops of DNA called plasmids which are
easy to transfer from one cell to another
82
Making Penicillin
Penicillin: an antibiotic produced by a fungus
Probes monitor temperature and pH
Air provides oxygen for aerobic respiration in fungus
Water-cooled jacket to maintain temperature
Stirrer allowing access to nutrients and oxygen while maintaining an even temperature.
83
biotechnology process (insulin)
- Isolation of the DNA making up a human gene using
restriction enzymes, forming sticky ends
- Cutting of bacterial plasmid DNA with the same restriction enzymes, forming complementary sticky ends
- Insertion of human DNA into bacterial plasmid DNA using DNA ligase to form a recombinant plasmid
- insertion of plasmid into bacteria
- replication of bacteria in a fermenter
84
classification shiz
king philip came over for gran's spaghetti
```
KINGDOM
PHYLUM
CLASS
ORDER
FAMILY
GENUS
SPECIES
```
