Stem cells

Question 1

what are the stem cells is plants called?

Answer 1

Meristems

Question 2

What is cambium?

Answer 2

cells that can differentiate into xylem and phloem

It is an example of a meristem.

Question 3

Basic structure of xylem

Answer 3

Dead, no cytoplasm, all space used for transport of water/minerals. strong cellulose cell walls and lignin support the xylem vessels, pits allow some lateral movement of water and support the natural movement of water, joined end to end.

Question 4

Basic structure of phloem

Answer 4

Sieve tube element sieve plate, thin cytoplasm wall, few organelles so easy to transport sugars
companion cell contains organelles the phloem needs to live, mitochondria-provide energy,

Question 5

Basic structure of palisade leaf cells

Answer 5

lots of chloroplasts-photosynthesis, vacuole-stores waste/sugars, long-large surface area, thin-lots can fit in a small space.

Question 6

what are erythrocytes?

Answer 6

Red blood cells

Question 7

what is the scientific name for red blood cells?

Answer 7

erythrocytes

Question 8

what are neutrophils?

Answer 8

white blood cells

Question 9

what is the scientific name for white blood cells?

Answer 9

neutrophils

Question 10

what are stem cells?

Answer 10

undifferentiated cells that have the potential to become specialised.

Question 11

what is differentiation?

Answer 11

the process in which cells differentiate and become specialised.

Question 12

what is the structure of erythrocytes?

Answer 12

Biconcave-larger surface area. lots of haemoglobin-works reversibly with oxygen and CO2. No organelles-more space for haemoglobin.

Question 13

what is the structure of neutrophils?

Answer 13

phagocytic- contain lysosomes, granular cytoplasm, multilobed nucleus.

Question 14

what is the structure of sperm cells?

Answer 14

Haploid nucleus, helical mitochondria, undulipodium, acrosome contains enzymes to digest the eggs wall.

Question 15

what is the structure of squamous epithelial cells?

Answer 15

have a basement membrane, very thin, allows rapid diffusion (shirt diffusion pathway)

Question 16

what is the structure of ciliated epithelial cells?

Answer 16

have a basement membrane, cilia waft substances away, mucus traps some substances. Goblet cells produce the mucus.

Question 17

what is special about embryonic stem cells?

Answer 17

they are totipotent (can differentiate into any cell)

Question 18

what does totipotent mean?

Answer 18

potential to differentiate into any type of cell.

Question 19

what does pluripotent mean?

Answer 19

potential to differentiate into any type of tissue

Question 20

what does multipotent mean?

Answer 20

potential to differentiate into any cells within a certain tissue.

Question 21

what does unipotent mean?

Answer 21

potential to differentiate into only one type of cell

Question 22

which cells are totipotent?

Answer 22

embryonic stem cells

Question 23

which cells are pluripotent?

Answer 23

umbilical cord

Meristematic

Question 24

which cells are multipotent?

Answer 24

Adult (Bone marrow)

Vascular (root and stem in plants)

Question 25

Which cells are unipotent?

Answer 25

Adult (skin)

Question 26

what ethical reasons are there against stem cell research?

Answer 26

Embryo is killed to produce cells.
Human life is sacred so shouldn’t be destroyed.
Human rights of embryo are violated
May increase risk of tumour formation

Question 27

what uses do stem cells have in treating diseases?

Answer 27

Can replace damaged tissues- treat Parkinson’s (embyonic)
Blood diseases (leukemia) (bone marrow/umbilical)
Skin graft (skin)
stem cell therapy (meristematic)

Question 28

What are the arguments for using embryonic stem cells?

Answer 28

Small number of embryos can make lots of cells for patients
Embryos would be destroyed regardless
No need for insulin injections
Reduce likelihood of rejection compared to injection
No issues with donor waiting list