Cell Differentiation and specialisation

Question 1

Undifferentiated cells are called

Answer 1

Stem cells

Question 2

What loses the ability to differentiate and what does not

Answer 2

Animals do

Plants don’t

Question 3

What is differentiation

Answer 3

When a cell changes to become specialized

Question 4

When cells change they develop…

Answer 4

Different subcellular structures and turn into different types of cells.

Allows them to carry out specific function.

Question 5

Cells that differentiate in animals are usually for…

Answer 5

Repairing and replacing cells

Skin and blood cells

Question 6

Sperm cells are specialized for REPRODUCTION

Function?

How?

Answer 6

Function - to get male DNA to female DNA.

Has a long tail and streamlined head to help it swim.

Lots of mitochondria providing energy needed.

Carries enzymes in its head to digest through egg cell membrane.

Question 7

Nerve cells are specialized for RAPID SIGNALING.

Function?

How?

Answer 7

Function - to carry electrical signals from one part of the body to another.

Cells are long (covers more distance)

Have branched connections at ends to connect to other nerve cells and form a network throughout the body.

Question 8

Muscle cells are specialized for CONTRACTION.

Function?

How?

Answer 8

Function - to contract quickly.

Cells are long (have space to contract).

Contain lots of mitochondria to generate energy needed.

Question 9

Root hair cells are specialized for absorbing WATER and MINERALS.

What are they?

How?

Answer 9

Cells on the surface of plant roots

Grow into long hairs that stick out into soil.

Give a big surface area for absorbing water and mineral ions from soil.

Question 10

Phloem and Xylem cells are specialized for TRANSPORTING SUBSTANCES.

What do they do?

How?

Answer 10

Form phloem and xylem tubes that transport substances such as food and water around plants.

Cells are long and joined end to end to make tubes.

Xylem cells are hollow in centre and phloem cells have very few subcellular structures so stuff can flow through them.

Question 11

The nucleus contains your ……….. in the form of ………

Answer 11

Genetic material

Chromosomes

Question 12

Chromosomes are c……… lengths of DNA m………

Answer 12

Coiled

Molecules

Question 13

Each chromosome carries a large number of genes.

These genes are different as they control the development of

Answer 13

Different characteristics

Question 14

Body cells have two copies of each chromosome (mum and dad)

So humans have two copies of…….. and
…………

Answer 14

Chromosome 1 and chromosome 2

Question 15

What is the cell cycle

Answer 15

When organisms divide to produce new cells

Question 16

What is the stage where the cell divides called?

Answer 16

Mitosis

Question 17

What is mitosis used for?

Answer 17

To grow or replace damaged cells

Question 18

The end of the cell cycle results in………

Answer 18

Two new identical cells to the original one with the same number of chromosomes

Question 19

What’s the first steps of the cell cycle?

Answer 19

Growth and DNA replication

Question 20

What must a cell do before it can divide?

Answer 20

Grow and increase amount of subcellular structures such as

MITOCHONDRIA

RIBOSOMES

Question 21

What happens when amount of subcellular structures has increased?

Answer 21

Duplicates DNA so there is one copy for each new cell.

DNA is copied and forms X shaped chromosomes

Question 22

First step of mitosis

Answer 22

Chromosomes line up at centre of cell and cell fibers pull them apart

Question 23

Second step of mitosis

Answer 23

Membranes form around each of the sets of chromosomes.

Becomes the nuclei of the two new cells,

The nucleus has divided

Question 24

Third step of mitosis

Answer 24

Cytoplasm and cell membranes divide.

Question 25

At the end of mitosis the cell has produced

Answer 25

Two new daughter cells

Contain exact same DBA
IDENTICAL

Their DNA is also identical to the parent cell.

Question 26

Where are stem cells found

Answer 26

In early embryos.

Can be turned into anything.

Question 27

Where are stem cells found in adults

Answer 27

Bone marrow

Can’t turn into any cell type at all only certain ones like blood cells

Question 28

Stem cells from embryos and bone marrow can be ……

Answer 28

Grown in a lab to produce clones

Made to differentiate into specialized cells to use in medicine and research

Question 29

Stem cells can transfer from a healthy persons bone marrow and replace

Answer 29

Faulty blood cells in another patient

Question 30

Embryonic stem cells can be used to

Answer 30

Replace faulty cells in sick people. Make insulin producing cells for people with diabetes

Question 31

Therapeutic cloning

Answer 31

Embryo can be made to have same genetic material as patient so the stem cells would not be rejected.

Question 32

Risks in using stem cells in medicine

Answer 32

Stem cells grown may become contaminated

Question 33

Why might someone be against stem cell research

Answer 33

Feel human embryos shouldn’t be used for experiments as it is a potential human life.

Feel there are other ways

Question 34

Why might someone be for stem cell research

Answer 34

Curing existing patients is more important than the rights of the embryo.

Embryos in research are usually the unwanted ones so ultimately they would be destroyed anyway

Question 35

Where are stem cells found in plants

Answer 35

Meristems (where plant growth occurs)

Question 36

Meristem tissues can

Answer 36

Differentiate into any type of plant cell

Question 37

In plants stem cells can be used to

Answer 37

Produce new clones of whole plants quickly and cheaply

Used to grow more rare plants

Grow crops of identical plants that have desired features e.g disease resistant