B5 - Growth And Devlopment Flashcards
Where does mitosis take place?
In the nucleus of body cells
Tissue is made up of…
Cells of the same type
e.g muscle cells - muscle tissue
Organs are made up of different …
Tissues grouped together eg the muscular tissue
Body systems are made up of …
Organs e.g the circulatory system
What is the term for fertilised eggs?
Zygote
Zygotes divide by mitosis to form what?
Embryo
What are embryonic stem cells?
Cup to and including the eight cell stage, cells are identical and can produce any kind of cell in the body.
When cells differentiate they…
Become specialised
What are adult stem cells?
Cells that can only differentiate to a limited number of cell types e.g bone marrow cells
how do cells become specialised?
Genes enable the cells to function by switching on that part of the gene. Any gene can be switched on.
What is xylem?
A specialised plant cell that transports water and mineral salts
What is phloem?
Specialised plant cell that transports the products of photosynthesis
Cells in regions called meristems are…
Unspecialised
When can plant cells differentiate into different types of cells?
When meristems cells have divided into two
In plants what are the only types of cells that divide?
Meristems
Where are meristems located in a plant?
The tip of shoots
Side buds
Length of plant stem and root
Tip of root
By decision of meristem cells followed by enlargement of one daughter cell, meristems produce growth in…
Height and width
Give examples of plant organs
Stems, roots, flowers, leaves
How do you do a plant cutting?
Take a section of a plant stem that includes parts of meristems and replant.
How do you produce a clone of a plant?
Doing a plant cutting
What is the name of a plant hormone that promotes plant growth?
Auxins
What is phototropism?
The plants response to the direction of light.
Where do auxins redistribute toward when a plant is exposed to light?
The shady side so it grows more, causing the plant to bend toward the light.
When are daughter cells produced?
When the cells divide by mitosis.
What are the two cells called that are produced by mitosis?
Daughter cells
What are gametes?
Sex cells
The process there the number of organelles increase is called cell growth an occurred when …
The DNA in each chromosome is copied
Cell growth is …
When the cell increases in size and the organelles increase as each chromosome is copied
The process of mitosis is …
When two daughter cells, each identical to their parent cell and containing an identical set of chromosomes are produced as the strands of each double chromosome separate and two nuclei are formed.
What is meiosis?
The type of cell devision produced by gametes
How is meiosis different to mitosis?
Cells with only half the number of chromosomes are produced
What process is essential in producing sex cells?
Meiosis
The process of miosis is…
Chromosomes are copied and pair up, cells divide into two, and divide into two again so there is one allele of each chromosome, producing gametes that contain 23 chromosomes.
That are the two steps the cell cycle involves?
Cell growth and cell devision.
What are organelles?
Structures in cells having a function
Describe cell devision
Two strands of the DNA in each chromosome seperate, two nuclei form, then the cytoplasm divides
Which cells in an organism have the same gene?
All of them
What is the dry tyre of DNA
Double helix
What are the rungs of the ladder in DNA called?
Bases
Bases always pair in the same way, what are these pairings?
A-T / T-A
C-G / G-C
How can you remember how bases are paired up?
@GingerCat.com
What are the order of bases in the gene instructions for?
The production of proteins
What type of cell can be switched on to produce any type of specialised cell?
Embryonic stem cells?
Which cells have the potential to produce cells to repair and replace damaged cells?
Embryonic and adult stem cells
Why is the use of embryonic stem cells the subject an ethical issue?
The embryo is destroyed. Some believe embryos have the right to life from when they are conceived.
What is mammalian cloning?
The switching on of a gene to produce the cell required under carefully controlled conditions.
What type of cloning has overcome some ethical issues of using enviro nix stem cells?
Therapeutic cloning
Wha does therapeutic cloning involve?
-put nucleus of a body cell in empty egg cell.
-Fuse together
Stimulate egg to divide and make nucleus.
What is mitosis?
Type of cell decision which produces new cells for growth and repair.
How do our cells make sure they only synthesise the proteins the need?
By switching genes on and off
Where does protein synthesis occur?
In the cyctoplasm
What carries the genetic to the cyctoplasm?
Messenger RNA (mRNA)
Hat does mRNA do?
Carry instructions for the order of proteins
Where are proteins assembled.
On organelles in the cytoplasm called ribosomes
What what happens when the order and sequence of the animo acids is different?
Different types of proteins are made, with different properties
What is the sequence of the animo acid determined by?
The genetic code
Where does RNA come from?
The DNA unzips and the messenger molecule (mRNA) copies the DNA
Why does mRNA have to be made?
DNA’s double helix is to big to leave the nucleus
Where does mRNA go once it leaves the nucleus?
It attaches to a ribosome
What is tRNA and what for it do?
It is transfer RNA which picks up a chemical signal from the mRNA and ferry’s animo acid to the ribosome where they are bonded together
What is the name of the process were proteins are made?
Protein synthesis
What is a zygote?
A fertilised egg
What are the units that make up DNA?
Bases, sugar, phosphates
