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Flashcards in Combined Biology - 4.1 Deck (52)
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Are animal and plant cells eukaryotic or prokaryotic?



Are bacterial cells eukaryotic or prokaryotic?



Q. What type of cell is shown in the diagram below?

Q. What key feature allows you to identify the cell below?

Q. Name the different parts of the cell.

• Bacterial cell

• The genetic material is not enclosed in a nucleus.


Name the different parts of the animal cell below


Name the different parts of the plant cell below.


Which cells are the smallest out of bacterial cells, animal cells and plant cells?

Bacterial cells


Match the following prefixes to the corresponding standard form.



Q. What is a plasmid?

Q. In which type of cells are plasmids found?

• A plasmid is a ring of DNA


• Plasmids are found in bacterial cells


Give the functions of the following cell parts:

a) Ribosomes

b) Mitochondria

c) Cell membrane

d) Nucleus

a) Ribosomes: Protein synthesis

b) Mitochondria: Where respiration happens

c) Cell membrane: Controls what goes in and out of the cell

d) Nucleus: Controls cells activity (where DNA is kept)


Q. Give the functions of the following cell parts:

a) Cell wall

b) Vacuole

c) Chloroplasts

d) Cytoplasm

a) Cell wall: Strengthens the cell

b) Vacuole: Contains cell sap (water, salts and sugars)

c) Chloroplasts: Where photosynthesis happens

d) Cytoplasm: Where chemical reactions occur


What is the main molecule that makes up cell walls?



Name three cell parts that are found in plant cells but not found in animal cells.

• Cell wall

• Chloroplasts

• Vacuole


How would you use the scale to estimate the size of the cell indicated by the arrow?

• Measure the width of the cell using a ruler, call this ‘a’.

• Measure the width of the scale using a ruler, call this ‘b’

• Divide ’a’ by ‘b’ then multiply the answer by the scale value (in this case 0.1 mm)


Name the following specialised animal cells and explain how they are adapted for their particular function.

a) Sperm cell: Long tail and streamline to help swim to the egg. Lots of mitochondria for energy. Enzymes in head to help digest into egg.

b) Nerve cell: Long with branched connections to form a network with other nerve cell.

c) Muscle cell: Long and contain lots of mitochondria to release energy for contraction.


Name the following specialised plant cells and explain how they are adapted for their particular function.

a) Root hair cell: Large surface area for absorbing water and minerals. Note: no chloroplasts as unable to photosynthesise under ground.

b) Xylem cell: Hollow cells that allow water and mineral ions to be transported.

c) Phloem cell: Not hollow, but have few sub-cellular parts to allow substances to flow through them


What is ‘differentiation’ ?

The process by which a cell becomes specialised


Animal cells differentiate at any early stage. How is this different to plant cells?

Many types of plant cells retain the ability to differentiate throughout life.


In mature animals, what is the main purpose of cell division?

For repair and replacement of cells


Q. Why is an electron microscope better than a light microscope?

Q. Why have electron microscopes been useful for understanding cell structure?

  • Better magnification, better resolution.


  • Cells can be seen in much finer detail, therefore scientists now know more about sub-cellular structures.


What equation links magnification, size of image and size of real object.

magnification=(size of image)/(size of real object)


The development of what piece of equipment has led to a better understanding of sub-cellular parts?

Electron microscope


Describe the stages of mitosis

• Cell grows and increases number of sub-cellular structures (e.g. ribosomes and mitochondria)

• DNA replicates to form two copies of each chromosome.

• One set of chromosome is pulled to each end of the cell and the nucleus divides.

• The cytoplasm and cell membranes divide to form two identical cells.


Why is cell division by mitosis important?

For growth and development


How is the DNA arranged within a nucleus?

Within chromosomes


What is a stem cell?

An undifferentiated cell that is capable of becoming a variety of other cells.


What are the two main places where human stem cells are found?

• Embryos

• Adult bone marrow


Why are embryonic stem cells more useful than stem cells from adult bone marrow?

Embryonic stem cells  are able to differentiate into a greater variety of cells.


Which type of stem cells are used to make blood cells and many other types of cells in an adult human.

Stem cells from bone marrow


Where are stem cells found in plants?

In the meristem tissue


Name two conditions that stem cells can be used to treat.

• Diabetes

• Paralysis