B2 Flashcards
What does the nucleus contain
Chromosomes
What do the chromosomes contain
Genes that cointain instuction to for making new cell which in turn makes tissue and organ.
Where is the gene found
In DNA
What are your characteristics a result of
Of many genes instead of just one gene.
A chromosome carries how many genes
Several hundred or even thousands
How many chromosomes do we have in a nucleus and how are they arranged.
We have 46 chromosomes and they are arranged in pairs so we have 23 pairs.
How are chromosomes inherited
In each pair of chromosomes one is inherited from your mother and one is inherited from your father
Sex cells are called what
Gametes
How many chromosomes do we have in a sex cell
23 in a total
What is the name of a series in which the body cell divide.
Cell cycle
What process does the cell cycle involve.
Mitosis
What does the cell cycle/mitosis result in
Two identical (daughter) cell.
What does it mean by the fact there is Two identical (daughter) cell
They have identical chromosomes and so the same genetic information.
What does cell division by mitosis needed for
Growth and development in multicellular organism or worn replacement of worn or damaged cell.
What happens in asexual reproduction.
The cells off the offspring are produced by mitosis from the cell of their parents. This why they are identical have no or little genetic variation
Is the cell cycles length varied
Yes it can be as short as 24 hours or as long as severely years
Where is cell cycle the fastest
As the baby is developing in the womb
When does the cell cycle slow down
After puberty is fished
Where does the cell cycle stay fast
In the hair follicles,the skin,the blood and the lining of the digestive system.
Stage 1 of the cell cycle
- This is is longest stage in the cell cycle.
- cells grow bigger and increase their mass
- they carry out their normal activities
- the form two copies of each chromosomes
- they also increase the number of sub-cellular structure( mitochondrial,ribosomes,and chloroplasts)
Stage 2 of the cell cycle
This is mitosis, each set of chromosomes are pulled toward each end of the dividing cel and the nucleus divides
Stage 3 of the cell cycle
In this stage the cytoplasm of the cell membrane divide to form form two identical daughter cell
What is mitotic cell division
This is cell division that is rapid and happens all the time like in skin
What is is it called when cells change into a different cell
Differenetiate
In early development plant and animal cells are unspecialised what is common name for them.
Stem cells
What can stem cell do.
Become any cell that is needed
When does most cells become specilised
Very early in life,by the time a baby is born most of its cells are specilised.
How are specialised cells specialised
as genes turn on and some genes turn off
How do specilised cells divide
Mitosis
Specialised cells can form only the…
The same type of cells
What differentiate cells cannot divide at all and what do they do too produce more cells
Blood cell and skin cells they use adult stem cells to produce more cells
What is special about plants cells
They are able differentiate all through their lives
Plant cells can…
Redifferentiate it can turn from one type of cell to another
Undifferentiate cells are formed where
At the meristems
What is a clone
Producing a identical offsping
Why is it difficult to clone animal
As cloning requires undifferentiated cell and animals cells become differentiated early in life’s
What do eggs cell and sperm cells combine too form
A zygote
Why do spinal injuries paryles
As nerve cells cannot be regenerated
Uses of stem cell
Can treat spinal injuries and other stuff as they can be any cell that is needed.
Stem cells in plants
Cloning plants quickly and economically, we can clone rare plants. we can also use this to research things on identical days
Why do people find stem cell unethical
As the come from embryos which are potential humans
What are the other issues with stem cells
It is slow difficult and expensive and we don’t know exactly it works.
