Page 6 question 2 2. Why is it important that the membrane of cells is in an adequate condition? What would happen if the condition of the membrane was altered? If the membrane was not in an adequate condition, it could affect the entry of nutrients and the release of waste products negatively. Also, the cell’s ability to interact with other cells and capture stimuli would also be affected negatively.

Page 6 question 3 3. Human red blood cells do not have genetic material. What consequences do you think this has for red blood cells? Given that red blood cells do not have genetic material, they cannot reproduce or carry out metabolic processes in an adequate way. As a result, red blood cells cannot live for a very long period of time.

Page 7 question 5 5. Why do cells need nutrients from the external environment? Nutrients are essential to carry out the biochemical reactions that cells need to carry out their vital activities.

Similarities: They both have a membrane, cytoplasm and genetic material. They also have the same type of biomolecules and perform the same vital functions.

Page 11 Initial questions: What are lysosomes? They are small vesicles that contain substances capable of digesting molecules.   ❚ What are vacuoles? They are structures that store different substances. ❚ How is the endoplasmic reticulum related to the Golgi apparatus? The Golgi apparatus takes substances from the endoplasmic reticulum, modifies them and secretes them. ❚ What are the two types of endoplasmic reticulum? The two types are: rough endoplasmic reticulum and smooth endoplasmic reticulum.

Page 12 Question 14 Find information and draw a diagram in your notebook that relates the endoplasmic reticulum to the Golgi apparatus.

INITIAL QUESTIONS FROM PAGE 11 AND 12 What are the names of the organelles that process nutrients? Vacuoles, lysosomes, endoplasmic reticulum and Golgi apparatus. ❚ What are the organelles that produce energy? Why can they function independently? They are mitochondria and chloroplasts. They can function independently because they have their own genetic information

Page 12. Q. 15 Similarities and differences between mitochondria and chloroplast Similarities: they both have a double membrane and their own genetic material. Differences: mitochondria have an inner layer that is folded and chloroplasts do not have this. Also, mitochondria carry out cellular respiration and chloroplasts carry out photosynthesis.

Page 12 questions 16 Is the following statement true? ‘Plant cells have chloroplasts instead of mitochondria.’ Explain your answer. No, it is not true. Chloroplasts are only found in plant cells, but mitochondria are found in both animal and plant cells.

Page 13 Q. 17 Define pseudopodia and phagocytosis. ❚ Pseudopodia: they are extensions of the cytoplasm produced as a result of viscosity changes. ❚ Phagocytosis: process in which a cell absorbs a particle from the external environment by producing pseudopodia to engulf the particle.

Page 13 Question 18 8. In your notebook, create a table that shows the differences between cilia and flagella according to their shape and movement.

Nucleus: “The Boss”. Page 14 What does it do? It controls what the cell does. (Genetic material) It’s a large organelle inside it (nucleolus) It has it’s own membrane: nuclear envelope with nuclear pores.

Page 14. Warm up activities What does the nucleus of the cell contain and what does it do? It contains genetic material and it is the control centre of the cell.   Why does the structure of the nucleus vary? It varies depending on the moment in the life of the cell.

Nucleolus is a round, dense structure where ribosomes are formed. Chromatin: It is a combination of DNA and proteins which makes up the genetic material. In cell division, chromatin condenses (makes Shorter) into chromosomes

Chromosome structure:

Chromosome structure:

How the Cell cycle works http://highered.mheducation.com/sites/007 2495855/student_view0/chapter2/animation __how_the_cell_cycle_works.html

Questions from Page 14 What happens during cell division? The nucleus changes completely; chromatin condenses into chromosomes.   What are the names of the two filaments that make up each chromosome? They are called chromatids. What is special about chromatids? They are both identical, so the genetic information is duplicated.

Page 14. Understand. Questions 21, 22, 23 21. Define the terms chromatid and centromere. Chromatid: half of one chromosome that contains all the genetic information. Centromere: the place where chromatids meet.  22. Discuss the following statement: ‘A cell with chromosomes does not have chromatin.’ Is it correct? It is correct, since chromosomes and chromatin are two different ways in which genetic material can be found. Chromatin transforms into chromosomes and back into chromatin during cellular division. If we observe chromosomes during mitosis, we would not see any chromatin. On the other hand, if we observed the interphase nucleus, we would not see chromosomes.  

Complete the sentences: a) Body cells have the chromosomes in pairs. These cells are known as ………………….. b) Egg and sperm cells are known as ……….. c) Egg and sperm cells have a single set of chromosomes. They are known as ……… cells. d) A gamete has …… the number of chromosomes that a body cells has. e)If the gamete of a mosquito has 3 chromosomes, how many chromosomes are there in the body cells? ………….. f) If the body cells of chickens have 18 chromosomes, how many chromosomes are there in the sperm cells? …………..

a) Body cells have the chromosomes in pairs a) Body cells have the chromosomes in pairs. These cells are known as diploid cells. b) Egg and sperm cells are known as gametes c) Egg and sperm cells have a single set of chromosomes. They are known as haploid cells. d) A gamete has half the number of chromosomes that a body cells has. e)If the gamete of a mosquito has 3 chromosomes, how many chromosomes are there in the body cells? 6 f) If the body cells of chickens have 18 chromosomes, how many chromosomes are there in the sperm cells? 9

Page 21. Biological importance of cell division

Page 20. Similarities and differences between mitosis and meiosis

Where process occurs in body MITOSIS MEIOSIS Purpose of division ……………... and repair Production of……….. ……….reproduction Where process occurs in body In all …………….cells Only in ……………….. Number of chromosomes in daughter cells after division …..……as in parent call ………the number in the parent cell Daughter cells are: ………. to parent Cell and each other ……… to parent cell and to each other

Where process occurs in body MITOSIS MEIOSIS Purpose of division Growth and repair Production of gametes/ sexual reproduction Where process occurs in body In all body cells Only in gonads-ovary & testis Number of chromosomes in daughter cells after division Same as in parent call Half the number in the parent cell Daughter cells are: Identical to parent cell & each other Different to parent cell & to each other

Complete the following sentences with the words mitosis or meiosis: a) The cell division that produces the sperm and egg is called …………………. b) The cell division taking place in all tissues for growth and repair is called ……………………. c) The cell division that occurs immediately after the ovum is fertilised by the sperm is called ……………….. d) The cell division that produces haploid cells is called …………………….. e) The cell division that produces diploid cells is called …………………………….

a) The cell division that produces the sperm and egg is called Meiosis b) The cell division taking place in all tissues for growth and repair is called Mitosis c) The cell division that occurs immediately after the ovum is fertilised by the sperm is called Mitosis d) The cell division that produces haploid cells is called Meiosis e) The cell division that produces diploid cells is called Mitosis

Content page: Page 6: 2,3 Page 7: 5 Page 8: 10 Page 9: 11 Page 19: 28 (in the book) Page 21: 31, 32 Page 22:37,38, 42, 45,50(book), 39, 43, 47, 48,49, 51, 53, 54,55