Answers
Oxford IB Biology Answers
- Course
- Institution
- Book
Answers for ib oxford biology textbook.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
Summary document of Chapter 5 Evolution and biodiversity IB Biology
-
Tema 3: Metabolismo
-
IB Biology Full Course Notes + Required Drawings Units 1 - 11 & Option D
9 reviews
By: stellaosorio • 7 months ago
By: shankarm • 2 year ago
Good
By: tortillachip44 • 3 year ago
By: wei-chengtung • 4 year ago
By: srinirnanduri • 5 year ago
By: alonso123456789 • 5 year ago
By: srikanntragvani • 6 year ago
A great book with thorough explanation and well presented diagrams
Seller
Follow
lilithstudiess
Reviews received
Content preview
OXFORD IB DIplOm a pROgRam m eANSWERS
2 0 1 4 ED I TI O N
BIOLO GY
C O U R S E C O M PA N I O N
Andrew Allott
David Mindorf
, W I T H I N TO P I C Q U E S T I O N S
Topic 1 - data-based questions
Page 6–7
magnification = size of image / actual size of the specimen; size of the image (scale bar) = 20 mm;
1. a)
actual size = 0.2 mm; magnification .2 = 100 ×;
b) width of thiomargarita in the image (image size) = 26 mm; magnification = 100 × actual
size = = 0.26 mm;
magnification = length mitochondrion in the image (63 mm = 63,000 µm) / actual size of the specimen
2. a)
(8 µm) = 63, = 7875×;
b) scale bar 5 µm × 7875 = 39 375 µm = 39.375 mm (approx 40 mm)
c) width on the image 23 mm / magnification 7875 = 0.0029 mm (2.9 µm)
3. a) 20 µm × 2000 (magnification) = 40,000 µm; (or 40mm scale bar)
b) actual size of specimen 34 mm / 2000 = 0.017 mm = 17 µm
4. a) hens egg is 7 mm wide in diagram; ostrich egg is 22 mm long in diagram; real hen egg is about
(50 × 22)
50 mm wide; ostrich egg: _ = 157 mm approx
7
7mm = 0.14×
b) magnification = size of image of egg / actual size of the egg; hens egg : _
50mm
Page 28
1. a central white/light area; sandwiched between two darker layers;
2. proteins appear dark in electron micrographs (page 27 of the text); phospholipids appear light;
reasonable support for the Davson-Danielli model;
3. proteins stain darkly; the dark pattern is the distribution of proteins; possible explanation is that
they are enzymes/cytoskeleton elements/protein bound vesicles;
4. magnification = size image / actual size of the specimen 1 mm/10 nm = 1 × 10-3 m/(10 × 10-9 m) =
0.1 × 106 = 100 000 × magnification
Page 29 (Membranes in freeze-etched electron micrographs)
1. a)
membrane proteins; that are transmembrane / straddle the membrane;
b) the Davson-Danielli model had proteins on the outside; provided evidence that there were proteins
in the centre of the membrane; falsified the Davson-Danielli model of membrane structure;
2. inner membrane; outer membrame visible to the right / outer membrane would not be as regular
in appearance;
3. mitochondria can be recognised by their rounded shape and cristae in these positions: lower right;
middle right; to the left of the mitochondrion middle right;
4. Golgi apparatus visible; with cisternae and many vesicles;
Page 29–30 (Diffusion of proteins in membranes)
1. Time (min) Mean
5 0
10 1.5
25 47
40 92
120 100
© Oxford University Press 2014: this may be reproduced for class use solely for the purchaser’s institute 1
, W I T H I N TO P I C Q U E S T I O N S
2. 100
mean % of cells with markers 80
fully mixed
60
40
20
0
0 20 40 60 80 100 120 140
time after fusion/minutes
3. as time progresses, an increasing number of cells have markers fully mixed
4. it supports the Singer-Nicholson model; membrane proteins can move; suggesting membrane is fluid;
5. range bars are a measure of variability of data; the more variable, the less reliable the conclusions
based on the data;
6. human body temperature (normal temperature for human cells);
7. the movement of markers increases with temperature, because the molecules move faster with
higher temperatures, then it levels off;
8. at lower temperatures the membrane proteins hardly move, therefore the markers are hardly mixed;
phospholipids in membrane not fully liquid / semi-solid;
9. ATP is required for active transport; the movement of membrane proteins is passive/it does not
require ATP/energy;
10. a rise in marker movement can be expected at lower incubation temperatures, since these animals
are adapted to a colder environment; have phospholipids with a lower melting point;
Page 36
1. 1 mm = 1000 µm; 400 µm × 1 mm / 1000 µm = 0.4 mm
2. a) decreasing with distance; sharply at first but then decreasing more gradually;
b) used by cornea cells for aerobic respiration; diffusion from the air is slow; no blood supply to bring
oxygen; no cells / no respiration in aqueous humour / oxygen supplied by blood capillaries in iris;
3. a) higher than the inner cornea; lower than the inner cornea;
b) concentration is lower in the cornea; there would not be (net) diffusion from the aqueous humour;
4. levels quickly fall off over a distance of 100 μm; making it an ineffective mechanism of transport
over larger distances;
5. a) increase in the distance O2 has to move; / decreasing concentration at the inner cornea;
b) increase moisture / increase O2 permeability of the lens;
6. an indication of the variability of the data; provides an indication of the reliability of the data;
Page 39
1. reduction in oxygen concentration below 21% reduces phosphate absorption; from 21% to 2.1%, the
reduction is very small / not significant; large / significant reductions below 0.9% / from 0.9 to 0.1%;
2. phosphate absorbed by active transport; ATP required for active transport; ATP produced by aerobic
respiration in roots; aerobic respiration requires oxygen;
3. phosphate absorbed mainly by active transport; when DNP blocks production of ATP by aerobic
respiration, phosphate absorption drops to a low level;
4. still some phosphate absorption when DNP has blocked ATP production by aerobic respiration;
some ATP might be produced by anaerobic respiration; active transport probably not the only
method of phosphate absorption; aerobic respiration fully blocked at 6 mmol dm-3 DNP, as
phosphate absorption does not drop any lower above this concentration;
© Oxford University Press 2014: this may be reproduced for class use solely for the purchaser’s institute 2
, W I T H I N TO P I C Q U E S T I O N S
Page 42
1. a) it moved into the tissues
b) out of the tissues
2. the cactus had the lowest concentration; where the graph crosses the x-axis is isotonic; lowest
isotonic value seen for the cactus;
3. cactus tissue might act as a water store, so has low solute concentration; pine kernel might have
dried out to become dormant, so has a high solute concentration; pine / butternut squash / sweet
potato might be adapted to habitat with higher solute concentrations in the soil; butternut squash /
sweet potato / pine kernel might contain large quantities of sugar / stored foods so have a high
solute concentration;
4. the starting masses might have been different in different tissue samples; percentage change is a
better measure of relative change;
Page 54
1. late anaphase; chromosomes have been separated into chromatids; chromatids are moving toward/
have arrived at the pole;
2. a) counting centromeres should give the number of chromosomes, thought it is difficult to
discern individual centromeres as they can appear as double dots; counting telomere dots and
dividing by two can yield a count but these can appear as single dots; reasonable estimate is
14 chromosomes;
b) union of gametes regardless of whether they are odd or even would yield an even number;
c) this is the same pattern that exists in anaphase; the pattern set up in interphase persists
throughout interphase;
d) shortening of telomeres ultimately might get to coding regions; death of the cell/limit to the
number of times a cell can divide;
Page 59
1. positive correlation between smoking and most diseases; respiratory, circulatory, stomach and
duodenal ulcers and cirrhosis of liver; no correlation with Parkinson’s disease;
2. respiratory diseases increased by a greater factor; over four times as high compared with less than
twice as high for circulatory with more than 25 cigarettes; number of deaths increased more by
circulatory; over 900 more deaths with circulatory and only 364 more with circulatory with more
than 25 cigarettes;
3. even a small number shows a doubling in respiratory diseases; and 1.5 times as much for
circulatory diseases; big difference between 1 cigarette a day and 14 cigarettes a day;
4. if a person was a smoker, they might have had other health limiting behaviours; such as drinking
(cirrhosis); or inactivity;
5. mouth cancer; lung cancer; esophageal cancer; stomach cancer; throat cancer.
© Oxford University Press 2014: this may be reproduced for class use solely for the purchaser’s institute 3
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lilithstudiess. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $18.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
81989 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now