Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
42 Cards in this Set
- Front
- Back
|
Where are genes |
In the nucleus |
|
|
Red blood cells don't have a nucleus so they can't |
Reproduce and can carry more haemoglobin (substance that binds with oxygen) |
|
|
Red blood cells are made where |
Bone marrow |
|
|
Red blood cells membrane is.. |
Thin so they can pick up oxygen and glucose to the muscles (they have bigger surface area to pick oxygen at the lungs) and absorb co2 at the muscles as a waste product |
|
|
Sperm has 3 adaptations |
Tail to swim to the egg Head to get through cell membrane Mitochondria to give energy |
|
|
What's the egg called after fertilisation |
Zygote |
|
|
DNA strands are made of lots of small units called |
Nucleotides |
|
|
Each DNA has four different bases |
Adenine (a) cytosine (c) guanine (g) thymine (t) |
|
|
DNA strands are made of lots of small units called |
Nucleotides |
|
|
Each DNA has four different bases |
Adenine (a) cytosine (c) guanine (g) thymine (t) |
|
|
What ones alway pair up (base paring) |
A-T G-C |
|
|
How do cells make proteins |
By joining amino acids |
|
|
Where and who makes proteins |
Made in the cell cytoplasm by organelles called ribosomes |
|
|
How do you get the information from the DNA to the ribosome |
A copy of the DNA is made using a molecule called Messenger RNA |
|
|
How do cells make proteins |
By joining amino acids |
|
|
Messenger RNA |
Similar to DNA but shorter and only one single strand |
|
|
What happens before a cell divides |
Copies everything so when it splits the two new cells will contain the right amount of material |
|
|
A cell splits into two by |
Mitosis |
|
|
Embryonic stem cells |
At the start all the cells in the embryo are the same and they can divide to produce any type of specialised cell this is until the 8 cell stage |
|
|
Differentation |
The process of stem cells becoming specialised |
|
|
What happens to most cells after the eight cell stage? |
Most of the stem cells in the human embryo start to differentiate |
|
|
Specialised cells most of the genes aren't.. |
Active they only produce the specific proteins they need |
|
|
Adult stem cells |
Already used to cure disease Bone marrow transplant |
|
|
Embryonic stem cells |
Can be extracted from very early human embryos. These could then be made to differentiate into specific cells to replace faulty cells in sick people. |
|
|
Cloning can be used to make stem cells |
Firstly you take an egg and remove its genetic material. The nucleus from a body cell of the adults your clothing is then inserted into the empty egg cell. Under the right conditions in active jeans in the nucleus of the body cell can be reactivated bracket (switched on) so that the embryo forms. embryonic stem cells can then be extracted from the embryo – these stem cells could then be controlled to form any type of specialised cell |
|
|
In plants the only cells that are mitotically active are found in plant tissues |
Called meristems |
|
|
Where are meristems found |
Area of the plant that is growing Roots and shoots |
|
|
Do meristem's produce unspecialised or specialised cells |
Unspecialised |
|
|
The unspecialised cells can become specialised and form tissues like xylem and phloem (the water and food transplant) |
These tissues can group together to form organs like leaves root stems and flowers |
|
|
Cutting |
Part of plant that has been cut off |
|
|
What's so good about cuttings? |
Cuttings are taken from a part of the plant where it's growing and this part contains unspecialised Merry stem cells which can differentiate to make any type of cell. Therefore a whole new plant can grow from one cutting which will then be a clone of the parent plant. |
|
|
What do gardeners often do? |
Take cuttings from parent plant that is pretty and then the plant is used to produce an identical copy |
|
|
Rooting powder |
Helps plant grow Contains hormones |
|
|
Phototropism |
When a plant grows towards a certain way usually light for a better life |
|
|
Positive phototropism |
Shoots grow towards light |
|
|
Negative phototropism |
Roots grow away from light |
|
|
Positive |
Mainly in the leaves Auxins go opposite side from the sun so the plant grows more towards the light |
|
|
Auxins are |
At the tip of the plant If a tip of a shoot is removed no sidings are available so the shoot may stop growing |
|
|
Gametes are produced because of meiosis |
It involves TWO DIVISIONS Produces new cells that only have half the original number of chromosomes Only happens in overalls and testicles |
|
|
MEIOSIS. FIRST DIVISION |
So the chromosomes have lined up at the centre of the cell The pairs have been pulled apart so each new cell only has one copy of each chromosomes You got a bit of mum and a bit of dad in each cell |
|
|
Meiosis SECOND division |
The chromosomes in the two different cells line up again and are pulled apart You get the gametes of each with only a single set of chromosome in it |
|
|
Meiosis SECOND division |
The chromosomes in the two different cells line up again and are pulled apart You get the gametes of each with only a single set of chromosome in it |
