cell specialisation and division

Question 1

what are specialised cells?

Answer 1

cells that have structures or adaptations that allow them to do a particular funcition

Question 2

cytokenisis meaning

Answer 2

cytoplasm splits

Question 3

what does pluripotent mean?

Answer 3

can differentiate into almost all types of cells

Question 4

what are stem cells?

Answer 4

unspecialized cells that differentiate into all types of cells in the body

Question 5

what are the 2 purposes of stem cells?

Answer 5

self renewal (copying)
differentiation (specialising)

Question 6

what are some uses for stem cells

Answer 6

-bone marrow transplant for leukemia
-treat disease
- fake meat (cow stem cells)

Question 7

difference between embryonic and adult sten cells

Answer 7

embryonic (3 to 5 days) are pluripotent
adult stem cells aren’t pluripotent

Question 8

functions of mitosis

Answer 8

• growth, and repair of tissues in multi cellular
• asexual reproduction in multicellular
• binary fission in unicellular

Question 9

how long does mitosis last (Percentage of cell life)

Answer 9

10%

Question 10

stages of mitosis (remember pmat)

Answer 10

prophase
metaphase
anaphase
telaphase

Question 11

what happens in prophase?

Answer 11

pre - dna replicates

Question 12

what happens in metaphase?

Answer 12

middle - line up on equator of cell

Question 13

what happens in anaphase?

Answer 13

away- move to poles of cell

Question 14

what happens in telaphase?

Answer 14

two - parent cell splits into 2 genetically identical daughter cells after cytokenisis

Question 15

pros of embryonic stem cells

Answer 15

-embryos that are usually wasted are used to help people
-many available
-pluripotent so can cure a wide variety of diseases

Question 16

cons of embryonic stem cells

Answer 16

-embryo right (no permission, pro life)
-relitavely untested and unreliable
-harm and death to embryo
-long term effect- cancerous?

Question 17

pros of adult stem cells

Answer 17

-relitevaly safe
-doesnt kill donors
-quick recovery
-Well tried and tested
-no ethical issues in collection (permission given)

Question 18

cons of adult stem cells

Answer 18

-painful to donors
-operation hazard (infection etc.)
-not pluripotent so depends on disease

Question 19

difference between chromatids and chromosomes

Answer 19

2 chromosomes joined together to make a chromatid

Question 20

how many chromosomes in humans?

Answer 20

46 in every cell EXCEPT sex cells ie sperm and egg cells

Question 21

cell specialisation- red blood cell

Answer 21

-biconcave disc shape
-large surface area
-no nucleus
-contain haemoglobin

Question 22

why do red blood cells have specialisation?

Answer 22

to be able to carry more oxygen

Question 23

cell specialisation- muscle cell

Answer 23

-elongated
-lots of mitochondria

Question 24

why do muscle cells have specialisations?

Answer 24

so they can contract

Question 25

cell specialisation-fat cell

Answer 25

-contain an energy store -can increase in size -very little cytoplasm

Question 26

why do fat cells have specialisation?

Answer 26

to be able to store energy

Question 27

cell specialisation- rod cell

Answer 27

-outer segment filled with visual pigment -many mitochondria -one end links up with a nerve cell

Question 28

why do Rod cells have specialisation?

Answer 28

so that you can see colour

Question 29

cell specialisation- egg cell

Answer 29

-can be enormous (biggest cell) -half the no. of chromosones

Question 30

why do egg cells have specialisations?

Answer 30

- half the amount of chromosomes so that when combined sperm it makes a full set

Question 31

cell specialisation- phloem

Answer 31

-elongated tubular shape with thin walled sieve tubes that have pores at each end in the cross wall and microtubules that extend between sieve material, allowing longitudinal flow of material

Question 32

cell specialisation - nerve cell

Answer 32

-long, thin -form connections with neurones and muscle cells -carry electrical impulses

Question 33

why are nerve cells specialised?

Answer 33

so they are able to carry messages around the body like an electrical circuit

Question 34

why are palised cells specialised?

Answer 34

help with photosynthesis

Question 35

cell specialisation- palised cell

Answer 35

-regular shape to pack tightly together -many chloroplasts containing chlorophyll

Question 36

cell specialisation- sperm cell

Answer 36

- half chromosomes bc it's a sex cell - acrosome contains digestive enzymes -many mitochondria -long tail

Question 37

why are sperm cells specialised?

Answer 37

so they can swim to egg cells, penetrate the cell wall and fertilise the egg cell

Question 38

cell specialisation- guard cell

Answer 38

Banana shape, found in pairs, contain chloroplast, ability to change shape

Question 39

cell specialisation- xylem

Answer 39

-form long hollow tubes -wall contain lignin, strengthening material -dead no cell contents

Question 40

cell specialisation -root hair cell

Answer 40

-thin cell wall -large surface area -many mitochondria for respiration

Question 41

cell organisation

Answer 41

cell - tissue - organ - organ system - organism

Question 42

what is a tissue?

Answer 42

a group of cells with a particular function many tissues have lots of similar types of cells to enable the tissue to fuction

Question 43

what is an organ?

Answer 43

tissues grouped together to carry out a specific function

Question 44

what is binary fission?

Answer 44

the form of cell division used by prokaryotes to reproduce asexually