Answer four questions only
Question (1)
A- Choose the correct answer
1- Scientist …….. stated that cells are produced from pre-existing ones.
A- Schleiden B- Virchow C- Robert Brown D- Charles Darwin
2-……. are plastids which are devoid of pigments
A- Leucoplasts B- Chromoplasts C- Chloroplasts D- Chromatin
3- The tissue which is responsible for transporting water and salts from roots to leaves.
A- Xylem B- Phloem C- Sclerenchyma D- Parenchyma
4- The cell walls of Sclerenchyma tissues cells are thickened with……..
A- Lignin B- Cellulose C- Chitin D- Glucose
5- ……. microscope works by sunlight and artificial light.
A- Electronic B- Light C- Stereo D- Digital
B- Give reasons for:-
1- Active transport plays an important role in plant cells.
2- The importance of electronic microscope
3- Nucleus is the most important organelle in cell
4- Epithelial tissues line the small intestines of living organisms
Question (2)
A- Write the scientific term
1- The movement of pure water molecules through a membrane from a region of low concentration to a region of high one.
2- A living tissue composed of rectangular cells, its wall are not thickened with Lignin but with cellulose.
3- Coloured pigments which exist in chromoplasts
4- They synthesize proteins in the cell.
B- What happens if
1- Cells didn't have smooth endoplasmic reticulum
2- Putting red blood cells in a solution with low concentration
3- Muscle cells didn't have many mitochondria
4- Removing the nucleus from the cell.
Question (3)
A- Match
Group (B) |
Group (A) |
A- Golgi body |
1- A thin membrane surrounding cytoplasm and controls the passage of substance to and from the cell |
B- Plasma membrane |
2- A kind of plant tissue which transports nutrients and water from roots to leaves |
C- Green plastids |
3- Thread- like structure which are composed of DNA combined with proteins |
D- Xylem |
4- A group of flat membranous sacs with spherical ends which exists in great no. in glandular cells |
E- Chromosome |
5- Cell organelles which exist only in plant cell and responsible for photosynthesis process |
F- Cell wall |
|
B- Write short notes about
1- Prokaryotic cells
2- Stem cells
3- Cell respiration
4- Cell theory
Question (4)
A- Correct the underlined words
1- The part of cell which is responsible for synthesizing lipids is Lysosomes
2- Scientist Rudolf Virchow stated that all plants are composed of cells.
3- Collenchyma tissue is responsible for storing nutrients in cells
4- Mitochondria controls cell division process.
B- Compare between
1- Mitochondria and Lysosomes
2- Parenchyma and Collenchyma tissues
3- Epithelial and connective tissues
4- Electronic and light microscope
Question (5)
A- Study the following figure, and answer the questions
1- What is the name of this organ, what is its importance.
2- Label the previous diagram
3- What happens to structure (2) during cell division process?
B- Calculate the magnification power of a compound microscope, the magnification power of its objective lens equal 40x and that of its eyepiece equals 15x
Question (1)
A- Choose the correct answer
1- Virchow 2- Leucoplasts 3- Xylem 4- Lignin 5- Light
B- Give reasons for
1- Because it allows the cells of roots absorb the ions of salt, although the concentration of ions in the soil is greater than that of cells
2- Because it has a magnification power of one million x, as it uses beams of electrons instead of light; which gives clearer photos with higher differentiation
3- Because it controls all the biological processes in the cell (including cell division process), its nucleolus produces ribosomes which synthesize proteins, and it has the hereditary material of the cell in the form of chromatin reticulum.
4- In order to allow the small intestine absorb digested food and water
Question (2)
A- Write the scientific term
1- Osmosis 2- Collenchyma 3- Carotenoids 4- Ribosomes
B- What happens if:-
1- The cell wouldn't be able to synthesize lipids, change carbohydrates into glycogen, or decrease the toxicity of poisonous substances.
2- Water molecules would transport from the solution (low concentration) to red blood cells (high concentration), which makes them expand and tear up.
3- Muscle cells would work improperly because they lack energy.
Question (3)
A- Match
1-B 2-D 3- E 4- A 5- C
B- Write short notes about:-
1- Prokaryotic cells:-
They are primitive cells which are less complex than eukaryotic (developed) cells, they don't have many cellular organelles (such as plastids, mitochondria, Golgi bodies…etc). The hereditary material of those prokaryotes are not surrounded by nuclear membranes as eukaryotes are. Bacteria are example on prokaryotes
2- Stem cells :-
They are cells which can form different types of specialized cells (cardiac cells, nerve cells, skin cells…etc). These cells are formed in the early stages of fetus. Scientists seek to used them in the treatment of diseases, as stem cells can be used to produce dopamine substance (which cure many diseases), they can form pancreatic cells that secret insulin to treat diabetes patients and heart tissues instead of damaged one to treat heart diseases.
3- Cell respiration
A group of chemical reactions that occur inside mitochondria to release energy from glucose molecules. Glucose molecules are broken into carbon dioxide, water
and energy (which is stored in the form of ATP compound)
4- Cell theory
Cell theory is one of the most important theories in modern science, it states that all organisms are composed of one or more cells, cells are produced from pre-existing ones and cell is the structural and functional unit of living organisms.
Question (3)
A- Correct the underlined words
1- Ribosomes 2- Schleiden 3- Parenchyma tissue 4- Nucleus
B- Compare between
Lysosomes |
Mitochondria |
- They contain digestive enzymes which help in digesting nutrients and getting ride of wasters. |
- They store respiration enzymes in cell - They store substances which contain energy. - They store energy in the form of ATP |
Collenchyma tissue |
Parenchyma tissue |
- Living tissue which is composed of semi-rectangular cells whose wall are thickened with cellulose - They support the plant and protect its inner tissues. |
- living tissue which is composed of spherical or ellipsoidal cells with thin and flexible walls. - It stores nutrients, perform photosynthesis and aeration processes. |
Connective tissues |
Epithelial tissues |
- they are tissues which connect between the tissues and organs of body, transport liquids inside it , or support the body
- They are composed of relatively distant cells, the intracellular spaces between them are filled by liquid, semi-solid, or solid substances
|
- They are tissues which cover the outer surface of the body and line its cavity
- They consist of a great number of attached cells with little intracellular substances between them |
Light microscope |
Electronic microscope |
- It has a magnification power of 1500 times - It depends in its works on sunlight or artificial light. |
- It has a magnification power of one million x (1000000) - It depends on beams of electrons controlled by electromagnetic lenses |
Question (5)
A- The diagram
1- Label
Name: Nucleus
Importance: Control vital processes inside the cell (including cell division process) – contains the hereditary material of cell – contains nucleolus which forms ribosomes which synthesize proteins.
2- Label the diagram
1- Nucleolus
2- Chromatin reticulum
3- Nuclear pore
3- It condenses forming thread-like structure called chromosomes, which are two chromatids attaching to each other at a point called centromere, chromosomes appear at Metaphase stage of cell division.
2- The problem
The magnification power = magnification power of eyepiece x that of objective lens = 15 x 40 = 600x