Cell Biology

HideShow resource information
Cell Theory (3)
living organisms are made of one or more cells, cells are the smallest units of life, all cells come from pre-existing cells
1 of 59
What are the exceptions to cell theory? (3)
Skeletal muscle, Giant Algea & Aseptate fungi
2 of 59
Skeletal Muscle
(300 or more mm long) made of fibers that are much larger than normal cells & contain many nuclei
3 of 59
Giant Algea
(as much as 100mm) consists of many small cells but only has one nucleus
4 of 59
Aseptate Fungi
consists of hyphae (thread-like structures) have many nuclei in their long threads
5 of 59
Name the functions of life (7)
Nutrition, Growth, Response, Excretion, Metabolism, Homeostasis, Reproduction
6 of 59
What happens as a cell grows larger?
surface area to volume ration becomes bigger
7 of 59
Advantages to being multicellular (2)
1) it can grow to a larger size 2) its cells can differentiate so that different cells do different jobs
8 of 59
When do emergent properties arise?
when the interaction of individual component produce new functions
9 of 59
Emergent Properties
new properties that emerge from the interaction of their cellular components (multicellular)
10 of 59
Allele
one of the possible forms of a gene (eye colour: gene for eye colour is the same for booth green and brown eyes BUT allele is different)
11 of 59
Genome
An organisms entire set of genes
12 of 59
Where can a multicellular organisms genome be found?
In every cell (though some genes may not be used or 'turned off'
13 of 59
When is a cell 'committed'?
Once it is has gone down a pathway of development and becomes fixed and cannot change to a different pathway
14 of 59
Stem cells
cells that have the capacity to divide and differentiate along different pathways
15 of 59
Three examples of stem cells of Stem Cells
embryonic stem cells, adult stem cells (bone marrow skin, liver) & umbilical cord blood or placenta of newborn
16 of 59
Advantages of using embryonic stem cells over adult stem cells
adult stem cells do not have the same capacity as embryonic stem cells to differentiate along different pathways
17 of 59
Ethical issues of using stem cells therapeutically
.Newborns cannot consent for stem cells to be harvested from their umbilical cord, .If an embryo dies from the procedure it can be argued as immoral
18 of 59
Counter-arguments to embryonic stem cell treatment
. Early stage embryo's are just a ball of cells, .They lack a nervous system- feel no pain .left over embryo's from IVF> better used for stem cells than just killed
19 of 59
examples of therapeutic stem cell use
Stargardt's muscular dystrophy & leukemia
20 of 59
Stargardt's muscular dystrophy
genetic disease (kids 6-12) Mutation in eye, causes mem. protein used for active transport malfunction Vision becomes worse Experiment done- Embryonic stem cells injected into eye Cells attach to retina and stayed there for 4 months Eyesight improve
21 of 59
Leukemia
Cancer- abnormal amount of white blood cells produce by bone marrow.
22 of 59
Stem cell treatment of Leukemia (4)
Large needle inserted into large bone of donor, fluid removed from bone marrow. Stem cells extracted and froze. High doses of chemo (kill cancer cells) .Donors stem cells returned to body.
23 of 59
1μm
0.001mm
24 of 59
1nm
0.001μm
25 of 59
Eukaryote
organisms whose cells contain a nucleus, associated with histone proteins
26 of 59
Prokaryote
organisms whose cells lack a nucleus, no membrane bound organelles and no associated histone proteins
27 of 59
Binary Fission
process in which prokaryotic cells divide
28 of 59
The process of Binary Fission
Bacterial chromosome is replicated. These move to opposite ends of the cell. wall and plasma pull inwards> two identical cell. binary fission can occur every 30 mins
29 of 59
Eukaryotic cells with a single membrane (5)
Rough endoplasmic reticulum, Smooth endoplasmic reticulum, Golgi apparatus, Lysosomes, Vesicles and vacuoles
30 of 59
Eukaryotic cells with a double membrane (3)
Nucleus, Mitochondrion, Chloroplast
31 of 59
Name main organelles of prokaryotes
Cytoplasm, Nucleoid (containing naked DNA), 70S Ribosomes, Pilli, Plasma membrane, Cell wall, Flagellum
32 of 59
Lysosomes
enzymes that hydolosise big molecule
33 of 59
Golgi apparatus
packages proteins into vesicles
34 of 59
Rough and Smooth Endoplasmic Reticulum
transports and synthesises proteins
35 of 59
Pro's and Con's to using adult stem cells
Pro's: fully compatible with adult stem cells, Con's: Difficult to obtain, Less potential than embryonic cells
36 of 59
Pro's and Con's to using embryonic stem cells
Pro's: Less chance of genetic damage/ mutation, Con's: more potential for tumor formation, chance of regection
37 of 59
The Davson-Danielli Model
(1930's) Model of membrane structure. There is a bilayer of phospholipids in the center of the membrane with layers of proteins on either side
38 of 59
Reason for Davson-Danielli Model (3)
1)Chem. analysis of membrane showed they were composed of phospholipids and proteins 2) Evidence suggested there was a phospholipid bilayer 3)Experiments showed layers of protein could act as a barrier
39 of 59
The Singer-Nicolson Model
(1950s-60s) evidence accumulated and falsified Davson-Danielli Model. Model currently used
40 of 59
What did the Singer-Nicolson Model show to falsify the Davson-Danielli Model? (3)
1)Micrographs showed globular proteins were in the center of phospholipid bilayer 2)Analysis of mem. proteins showed some parts were hydrophobic 3)Fusion of cells w/ mem. proteins taged w/ coloured markers showed proteins can move in mem. colours mix
41 of 59
Intergral proteins
embedded in the phospholipid bialyer
42 of 59
Peripheral proteins
attached to outer surface of the phospholipid bialyer's membrane
43 of 59
Glycoproteins
sugar units attached onto the outer surface of the phospholipid bialyer's membrane
44 of 59
Phospholipids
basic component of all biological membranes
45 of 59
Amphipathic molecule
Part of molecule is attracted to water (hydrophilic) ans part is not attracted to water (hydrophobic)
46 of 59
What happens when phospholipids are mixed with water?
They naturally become arranged into bilayers, hydrophilic heads facing outwards.
47 of 59
Cholesterone
restricts movement of phospholipid molecules (reduces fluidity and permeability of membrane)
48 of 59
Diffusion
passive movement of particles from a region of high concentration to a region of low concentration
49 of 59
Diffusion can occur across a membrane if...
there is a concentration gradient and the membrane is permeable to the particle
50 of 59
Partly permeable membranes
allow some substances to diffuse through but not others
51 of 59
Facilitated diffusion
the passive movement of molecules across the cell membrane via the aid of a membrane proteins (channel and carrier proteins)
52 of 59
Simple diffusion
passive movement along a gradient, which will continue until molecules become evenly dispersed (equilibrium)
53 of 59
Passive transport
the movement of material along a concentration gradient (high concentration ⇒ low concentration)
54 of 59
Active transport
the movement of materials against a concentration gradient (low concentration ⇒ high concentration)
55 of 59
Describe sodium and potassium channel proteins in membranes
They are in the membranes of neurons that open and close, depending on the voltage across the membrane. They are voltage-gated membranes and are used to transmit nerve impulses
56 of 59
Where in the nervous system are potassium channels contained?
The axons of neurons that are used during an action potential
57 of 59
Channel proteins
one allow one type of substance to pass through the membrane (specific)
58 of 59
Function of potassium channels in axons
They are
59 of 59

Other cards in this set

Card 2

Front

What are the exceptions to cell theory? (3)

Back

Skeletal muscle, Giant Algea & Aseptate fungi

Card 3

Front

Skeletal Muscle

Back

Preview of the front of card 3

Card 4

Front

Giant Algea

Back

Preview of the front of card 4

Card 5

Front

Aseptate Fungi

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Cellular processes and structure resources »