Cloning

Question 1

A clone

Answer 1

-DNA fragments, cells, tissues or organisms that are genetically identical

Question 2

How are clones formed in nature?

Answer 2

By asexual reproduction

Question 3

Molecular cloning

Answer 3

Cloning to make identical genes and useful chemical compounds

Question 4

Traditional methods of plant cloning

Answer 4

• plant cuttings and grafts
• replanting bulbs and tubers

Question 5

Plant tissue cultures

Answer 5

growing plants from cells or tissues of a parent plant in a special growth medium

Question 6

Name at least 3 plant organs for asexual reproduction

Answer 6

runners

bulbs

tubers

leaf plantlets

suckers

Question 7

A typical plant tissue culture medium

Answer 7

• A glass container with a solid or liquid culture substance
• It contains nutrients and hormones that promote mitosis

Question 8

Explain what a callus of cells is in a plant tissue culture

Answer 8

• Isolated plant cells from parent plant divide by mitosis
• These form a group of cells called a callus
• With more plant hormones the callus differentiates into roots, stems and leaves

Question 9

Advantages to making plant tissue cultures

Answer 9

• exact copies with wanted traits
• fast growth to mature plants
• increased quantity of plants possible
• virus-free stock

Question 10

The first cloned animals, when?

Answer 10

Sea urchins Late 1800s

Question 11

First reproductively cloned animal, when?

Answer 11

A sheep named Dolly, 1996

Question 12

How is a reproductively cloned animal made?

Answer 12

• Donor egg cell taken from foster mom
• Nucleus removed
• Cell taken from animal to be cloned
• Nucleus removed and fused with the empty egg cell
• Fused cell divides by mitosis to form embryo
• Embryo placed in foster mothers uterus to develop into cloned individual.

Question 13

Therapeutic cloning

Answer 13

Cloning to form stem cells

Able to grow into specific tissues

Needed to replace diseased tissues

E.g. skin for burns

E.g. bone marrow transplants for cancer

Question 14

Embryonic stem cells

Answer 14

Embryonic tissue cells

Can produce more of themselves

Can differentiate into all cell types

Question 15

Adult stem cells

Answer 15

• Tissue stem cells
• Replace old and damaged cells in adults
• Only certain types

E.g. skin stem

E.g. bone marrow

E.g. Nerve tissue

Question 16

“in vitro” stem cells

Answer 16

fertilised eggs grown in cultures

Question 17

“in vivo” stem cells

Answer 17

fertilised eggs grown in the mother

Question 18

Three sources of stem cells

Answer 18

Embryo’s

Umbilical cord or placenta

Bone marrow and liver tissue

Question 19

Possible ethical opinions FOR stem cell research

Answer 19

• Embryos are clumps of tissue, not yet humans
• Umbilical cord blood does not destroy embryo’s
• Reproductive cloning produces stem cells without need for fertilisation
• Research needed for numerous benefits

Question 20

Possible ethical opinions AGAINST stem cell research

Answer 20

• New life begins with fertilisation
• Destruction of embryos is immoral, equates murder
• taking role of God in creating and destroying life