key terms Flashcards
(167 cards)
1
Q
a light microscope
A
a tool that uses beams of light and optical lenses to magnify objects
2
Q
an electron microscope
A
a tool that uses beams of electrons and magnetic lenses to magnify specimens
3
Q
magnification
A
a measure of how much bigger an object is than the real object
4
Q
resolution
A
how close two objects can be before they are seen as one
5
Q
transmission electron micrographs
A
micrographs produced by electrons that give 2d images like electron microscopes but with higher magnification
6
Q
scanning electron micrographs
A
micrograph produced by electron microscopes that have lower mag than transmission ones but seen in 3d
7
Q
organelles
A
sub cellular bodies found in cytoplasm of cell
8
Q
eukaryotes
A
group of organisms with cells that have genetic material enclosed in membrane
9
Q
prokaryotes
A
group of organisms with genetic information not enclosed in membrane bound organelle
10
Q
cell surface membrane
A
membrane that forms the outer bound of the cytoplasm and controls what goes in and out of the cell
11
Q
vesicles
A
membrane bags that hold secretions made in cells
12
Q
polar liquids
A
lipids with on end attached to a polar group
13
Q
gated channels
A
protein channels through the bilipid layer opening and closing depending on activity
14
Q
fluid mosaic model
A
current model for the phosphobilipid layer
15
Q
cytoplasm
A
jelly like substance that makes bulk of cell and contains organelles
16
Q
nucleus
A
contains genetic material surrounded by nucleus pores
17
Q
protoplasm
A
cytoplasm and nucleus combined
18
Q
chromatin
A
granular combination of dna bonded to protein found in nucleus when cell not actively not dividing
19
Q
nucleolus
A
dense area of almost pure dna where ribosomes are produced and where division and growth occur
20
Q
cristae
A
infoldings of inner membrane which provide large surface area for aerobic respiration
21
Q
eubacteria
A
true bacteria
(prokaryotes and organisms)
22
Q
endosymbiotic theory
A
suggests mitochondria and chloroplasts lived as independent organelles before living sybmbiotically with other organisms
23
Q
centrioles
A
bundle of tubules found near the nucleus involved in cell division by production of a spindle of microtubules that move to each side of the cell
24
Q
spindle
A
set of overlapping microtubules running length of the cell formed as centrioles pull apart in meioisis and mitosis
25
cytoskeleton
dynamic 3d web like structure made of microfilaments that keep web in place and keeps organelles bound
26
microfilaments
protein fibres that make up part of cytoskeleton
27
microtubules
protein fibres 20mm in diamater that make up part of cytoskeleton
28
vacuole
fluid filler cavity in cytoplasm of cell surrounded by a membrane
29
endoplasmic reticulum
3d network of membrane bound cavities that link to nuclear membrane and makes up large part of transport and synthesis
30
contracile vacoules
vacuoles that can fill and are empty to help control concentration of cytoplasm of simple freshwater animals
31
80s ribosomes
found in eukaryotes
site of protein synthesis
made of 60s and 40s
have ribisomal RNA
32
70s ribosomes
found in prokaryotes
33
rough endoplasmic reticulum
ER that is covered in ribosomes involved in production and transport of proteins
34
exocytosis
energy requiring process where vesicle fuses with cell surface membrane so contents are released outside the cell
35
smooth endoplasmic reticulum
smooth tubular surface without ribosomes involved in transport of steroids and lipids
36
golgi apparatus
stacks of membranes that modify proteins made elsewhere in cell and package them to transport them
37
lysosome
organelle full of digestive enzymes used to break worn out cells or digest simple foods
38
apoptosis
programmed cell death
break down of worn out damaged cells by lysosomes
39
cell wall
freely permeable membrane around plant cells mainly made of cellulose
40
suberin
chemical that impregnates cellulose cell walls in cork tissues and make them impermeable
41
lignin
chemical that impregnates cellulose cell wall in wood and makes it impermeable
42
middle lamella
first layer of plant cell to be formed when plant cell divides
mainly made of calcium pectate that binds layers of cellulose together
43
pectin
polysaccharide tht holds cell walls of neighouring plant cells together and is part of primary structure of plant cell wall
44
primary cell wall
first very flexible plant cell to form with all cellulose microfibrils oriented in a similar direction
45
secondary cell wall
older plant cell wall in which the cellulose microfibrils built in different angles to each other making cell wall more rigid
46
plant fibres
long cells with cellulose cell walls that have been heavily lignified so they are rigid and very strong
47
plasmodesmata
cytoplasmic bridges between plant cell walls that allow comunication between cells
48
symplast
interconnected cytoplasm of plant cells connected by plasmodesmata
49
tonoplast
specialised membrane that surrounds the permanent vacoule in plant cells and controls movement of substances in and out of cells
50
cell sap
aquaous solution that fills vacoule
51
chloroplast
organelle adapted to carry out photosynthesis contaning green pigment chlorophyll
52
amyloplast
plant organelles that store starch
53
tissue
group of specialised cells carrying out specific function
54
epithelial tissue
tissues that form the lining of surfaces inside and outside the body
55
hypertonic solution
solution with higher concentration of solutes and lower concentration of water than surrounding solution
56
peptidoglycan
large net like molecule found in all bacterial cell walls made up of many parralel polysaccharide chains with short peptide cross linkages
57
pili (fimbriae)
thread like protein projections found on surface of some bacterias
58
bacteriophages
viruses that attack bacteria
59
flagella
many stranded helices of the contracile protein flagellin found on some bacteria. they move the bacteria by rapid rotations
60
mesosomes
infoldings of cell membrane of bacteria
61
nucleiod
area in a bacterium wheree we find single length of coiled dna
62
plasmids
small circular pieces of dna that code for specific aspects of the bacterial phenotype
63
gram staining
staining technique used to tell apart bacteria type from cell walls
64
gram positive bacteria
bacteria that have technioc acid in cell walls and stain purple blue with staninng
65
teichoic acid
chemical found in cell walls of gram positive cell
66
gram negative bacteria
bacteria that have no techoic acid in cell wall and stain red during staning
67
cocci
spherical bacteria
68
bacilli
rod shaped bacteria
69
spirilla
bacteria with twisted or spiral shape
70
vibrios
comma shaped bacteria
71
obligate aerboes
organisms that need oxygen for respiration
72
envelope
coat outside a virus derived from lipids in the host cell
73
capsid
protein coat of a virus
74
capsomeres
repeating protein units that make up capsid in virus cell
75
virus attachment particles
antigens that target proteins in host cells surface membrane
76
Dna viruses
composed of dna as genetic material
77
rna viruses
composed of rna as genetic material
78
retroviruses
special type of rna virus that controls the production of dna corresponding to viral rna and insert it into the host cell dna
79
reverse transcriptase
enzyme synthesised in the life cycle of a retrovirus that makes dna corresponding to viral rna genome
80
non virulent
micro organism that doesnt cause disease
81
provirus
dna thats inserted into host cell during lysogenic pathway of production of viruses
82
lysogeny
period when cell virus doesnt effect host
83
latent
state of non virulent cell within host cell
84
ebola
highly infectious disease that causes fever and internal bleeding and death in half cases
85
mortality rate
measurment of the number of deaths in a given population or due to a specific case
86
pandemic
epidemic that takes place in several places or globally
87
mitosis
process by which a cell divides and produces two daughter cells
88
asexual re produces
geneticlly indentical produce
89
meiosis
gametes making sexually different organisms
90
histones
positively charged proteins involved in coiling of dna to form dense chromosomes in cell division
91
nucleososomes
dense clusters of dna wound around histones
92
karyotype
way of displaying images of chromosomes of a cell to show pairs of autosomes and gametes
93
cell cycle
regulates process in which two daughter cells are produced
94
interphase
period between active cell division when cells increase their size and mass replicate dna and are in normal stage
95
chromatid
one strand of dna joined with other chromatids in centrosomes
96
cyclins
small proteins that vuild up during interphase and involved in control of cell cycle by their attachment to cyclin dependent kinases
97
cyclin dependent kinases
enzymes involved in control of the cell cycle by phospholyrating other proteins activated by atatchment to cyclins
98
prophase
first stage of cell division where chromosomes are coiled up and consist of the daughter chromatids joined by the centromere. the nucleoluus breaks down
99
metaphase
second stage of active division where a spindle of overlapping protein microtubules form and chromatids line up on the metaphase plate
100
anaphase
third stage
where centromeres split so chromatids become new chromosomes.
moved to opposite sides
centromeres first
by contractions of microtubules of spindles
101
telophase
where nuclear membrane forms around two sets of chromosomes
chromosomes unravel and spindle breaks down
102
centromere
region where a pair of chromatids joined which attached to single strand of spindle at metaphase plate
103
metaphase plate
region of spindle in middle of cell where chromosomes line up
104
cytokenesis
division of cytoplasm to make two daughter cells
105
clones
genetically identical offspring produced as a result of natural or artificial asexual reproduction
106
binary fission
splitting of one individual to form other individuals
107
sporulation
production of asexual spores that can grow into individuals
108
regeneration
use of mitosis to regrow a body part that has been lost
109
fragmentation
use of mitosis to regenerate whole organism with fragment of an animal
110
budding
outgrowth from parent organism which develops into individual via mitosis
111
vegetative propogation
a plant forms a structure by mitosis that develops into a fully differentiated genetically identical new plant
112
parthenogenesis
an unfertilised egg develops into a new individual
113
dry mass
mass of an organism where all water is removed from
114
meristem
region of mitosis and growth in a plants shoot or root
115
diploid
cell with nucleus containing full set of chromosomes
116
haploid
cell with once complete set of chromosomes
117
zygote
cell formed when to haploid cells fuse at fertilisation
118
fertilisation
fusing of two haploid cells to form diploid zygote
119
polypoidy
when cell or organism has more than two sets of organisms
120
gonads
sex organs in animals
121
anthers
sex organs in plants
122
pollen
produced in anthers
has haploid male gametes in plants
123
ovules
formed in overies
have haploid female gametes in plants
124
testes
male sexual organs
125
spermatoza
haploid male gamates in animals
126
ova
haploid female gamates in animals
127
microspores
result of meiosis in plants that produce male gametes pollen
128
megaspores
result of meoisis in plants that produce female gametes in plantes ovula
129
chiasmata
points where chromosomes break during recombination
130
translocation
part of chromosome breaks of and joins different chromosome
131
sex chromosomes
with haploid nucleus that determine sex of offspring
132
non disjunction
when chromosomes fail to seperate and copy so one has copy and one doesnt
133
monosomy
when only one member of pair of chromosome present in cell
134
polysomy
when cell contains three or more of same chromosome
135
aneuploidy
when cell has to many or few chromosomes
136
mutation rate
rate at which mutation naturally occurs
137
mutagens
chemicals known to increase rate of mutation
138
gameotegenesis
formation of gametes in sex organs
139
primordial germ cell
cells that divide by meosis do form sperm and ova
140
spermatogenesis
formulation of sperm in testes
141
oogenesis
formulation of ova in ovaries
142
sporophyte generation
diploid generation in plants that produce spores by meiosis
143
gametophyte generation
haploid generation in plants that gives rise to gametes by mitosis
144
sporophyte
diploid main body of plant
145
pollen sacs
parts of anthers where pollen grains develop
146
tube nucleus
male nucleus where that will control production of pollen tube in fertilisation
147
generative nucleus
male nucleus that will fuse with female nucleus
148
pollen tube
tube that grows out of pollen grain down style into ovary and through micropyle of ovule to carry two male nuclei to the ovule
149
placenta
pad of special tissue that attaches plant ovule to the ovary wall
150
pollination
transfer of pollen from anther to stigma
151
external fertilisation
process of fertilisation of female gamete by male gamete met outside parental bodies to fuse and fertilise
152
internal fertilisation
fertlisation of female by male inside mothers body
153
acrosome
region of head that has enzymes to digest layer of ova
154
zona pelludica
layer of protective jelly around infertilused egg cell
155
polyspermy
fertilisation of egg by more than one sperm
156
fertilisation membrane
tough layer formed outside egg to stop more sperm getting in
157
conception
fertilisation of sperm in humans
158
germination
pollen tube start to grown out of pollen grains to transfer male nuclei to ovule
159
double fertilisation
one male nucleus fuses with nuclei of two polar nuclei to form endosperm nucleus and fuses with egg cell to form diploid zygote
160
totipotent
cell is able to develop into any type of cell
161
cleavage
special type of mitosis with no interphase to have lots of undifferentiated cells
162
blastocyst
hollow ball of cells 5 days after fertilisation
163
embryonic stem cells
cells in early stage embryo that have potential to form many other cells
164
pluripotent
cell is able to develop into most other cells
165
pluripotent embryonic stem cells
cells that can form most but not all types of cells
166
cell determination
pedestination of cells to become type of tissue depending on position
167
diffrentiate
develop into specific type of tissues
