IB Biology I – Mitosis Practice #3		Name: ____________________________ Block: ___
1.	According to cell theory all cells arise from pre-existing cells.   The following diagram shows the cell cycle of a eukaryotic (body) cell of a diploid organism.

(a)	Define the term diploid.
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(1)
(b)	Identify the parts of the cell cycle labelled A and B.
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(1)
(c)	State three activities that occur during part A of the cell cycle.
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(d)	Outline the differences in cytokinesis in animal and plant cells.
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(e)	Explain the significance of complementary base pairing in relation to the cell cycle.
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(3)

2.	(a)	Before cell division in unicellular and multicellular organisms, the nucleus must divide to produce two genetically identical nuclei. Explain the events that occur in cells that result in the production of genetically identical nuclei.
(8)

(b)	Cell division in unicellular organisms can increase the population size. Outline reasons for the population of a unicellular organism not increasing, despite reproduction by cell division.
(6)

(c)	Suggest why cell division is necessary in multicellular organisms.
(4)

3.	(a)	State two processes which involve mitosis.
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(b)	Explain the importance of the surface area to volume ratio as a factor limiting cell size.
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(c)	State one difference between the proteins produced by free ribosomes and those produced by ribosomes attached to the endoplasmic reticulum.
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IB Biology I – Mitosis/Meiosis Practice #4		Name: _________________________________Block:___
1.	(a)	Explain the relationship between Mendel’s law of segregation and meiosis.
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(b)	Distinguish the differences between animal cells and plant cells undergoing mitosis and cytokinesis.
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2.	(a)	Variation occurs at the species level. Explain how sexual reproduction promotes variation in species.
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(b)	Explain how differentiation results in a variety of different types of cells occurring in a multicellular organism.
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 (3)
3.	Draw diagrams to show the four stages of mitosis in an animal cell with four chromosomes. 
(Total 5 marks)

4.	Outline the differences between the behaviour of the chromosomes in mitosis and meiosis. 
(Total 5 marks)

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5.	Describe, with the aid of a diagram, the behaviour of chromosomes in the different phases of meiosis.

(Total 5 marks)

6.	Describe how sexual reproduction promotes genetic variation within a species.
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 (Total 4 marks)
7.	Explain how meiosis results in great genetic variety among gametes.
(Total 8 marks)
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8.	Which phases of mitosis are shown in diagrams I and II?

		I	II

	I	II	
A.	metaphase	prophase	
B.	metaphase	telophase	
C.	anaphase	prophase	
D.	anaphase	metaphase	

9.	Colchicine is a chemical substance that prevents the formation of microtubules. What stage of mitosis would be prevented, if dividing cells were treated with colchicine?
A.	Breaking down of the nuclear membrane
B.	Replication of DNA
C.	Separation of genetically identical chromosomes (chromatids)
D.	Supercoiling of chromosomes
10.	Which processes always occur in meiosis but not normally in mitosis?
I.	Chiasmata formation
II.	Recombination of genes
III.	Separation of homologous chromosomes
A.	I and II only
B.	II and III only
C.	I and III only
D.	I, II and III
11.	Which of the following processes take place during interphase?
I.	Respiration
II.	Active transport
III.	Protein synthesis
IV.	Replication of DNA
A.	I only
B.	I and II only
C.	I, II and III only
D.	I, II, III and IV

12.	If a cell plate is beginning to form and nuclei are re-forming at opposite ends of a cell, what kind of cell is this?
A.	An animal cell in prophase
B.	A plant cell in prophase
C.	An animal cell in telophase
D.	A plant cell in telophase
13.	(a)	Define the term diploid.
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	(b)	Define the term haploid.
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	(c)	Outline how these terms relate to mitosis and meiosis. 
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(4)

IB Biology I – Mitosis/Meiosis Practice #5		Name: _________________________________Block:___
1.	Explain genetic variety in meiosis and how it is accomplished.
(Total 6 marks)
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_____2.	Which response describes the behaviour of chromosomes in metaphase I and anaphase II of meiosis?
	Metaphase I	Anaphase II	
A.	Chromosomes line up at the equator	Separation of homologous chromosomes	
B.	Tetrads (bivalents) line up at the equator	Separation of homologous chromosomes	
C.	Chromosomes line up at the equator	Separation of sister chromatids	
D.	Tetrads (bivalents) line up at the equator	Separation of sister chromatids	
3.	Compare and contrast mitosis and meiosis.
(Total 5 marks)
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_____4.	A cell with a diploid number of 12 chromosomes undergoes meiosis. What will be the product at the end of meiosis?
A.	2 cells each with 12 chromosomes
B.	4 cells each with 6 chromosomes
C.	2 cells each with 6 chromosomes
D.	4 cells each with 12 chromosomes
_____5.	Which process results in the greatest genetic variation in a population?
A.	Meiosis
B.	Mitosis
C.	Cytokinesis
D.	Natural selection
_____6.	The diagram below shows the life cycle of a moss. The haploid chromosome number is shown as n and the diploid number as 2n. At which stage in the life cycle does meiosis take place?

A.	I
B.	II
C.	III
D.	IV
_____7.	Which processes always occur in meiosis but not normally in mitosis?
I.	Chiasmata formation
II.	Recombination of genes
III.	Separation of homologous chromosomes
A.	I and II only
B.	II and III only
C.	I and III only
D.	I, II and III 

8.	Describe the process of active transport and passive using examples.
(Total 4 marks)
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9.	Which of the following correctly describes exocytosis?
	Plasma
membrane
increases in size	Plasma
membrane is
pulled inwards	Membranes fuse	vesicles
move away
from plasma
membrane	
A.	No	Yes	No	Yes	
B.	Yes	No	Yes	No	
C.	No	Yes	Yes	Yes	
D.	No	No	No	Yes	

(Total 1 mark)
10.	State one function of each of the following organelles.
	·	Lysosome
·	Golgi apparatus
·	Rough endoplasmic recticulum
·	Nucleus
·	Mitochondrion

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(Total 5 marks)

11. 	(a) Annotate the structure below. 

(4)

(b) Calculate the actual length of the cell, showing your working.

Answer:	...................................................................................................................
(2)
12.	Explain, with the aid of a diagram, how the structure and properties of phospholipids help to maintain the structure of cell membranes.
(Total 9 marks)