unit 2 Multicellular organisms Flashcards
what are the stages of mitosis
- chromosones double to form two idnetical chromatids
- they line up at the equator of the cell
- spindle fibres attatch to the chromatids
- The chromatids get pulled appart by the spindle fibres to different poles of the cell
- a new nucleus is then formed at each pole of the cell.
- two genetically identical cells are made with the correct chromatid number.
What is a feature of stem cells
They are unspecialised & divide by mitosis
Name the neurons
Sensory, inter and motor
What is the gap inbetween called
Synapse
How do the nuerons pass the message over the gap
Using diffusion of chemicals
What does the cerebellum do
Controls balance
What does the cerebrum do
Controls thought, emotions and memory
What does the medulla do
Controls breathing
what does a reflex action provide
Rapid automatic protection
Explain the process of fertalisation
The nucleas of the male gamete fuses with the nucleus of the female gamete
What are alleles
Different types of genes
What is the reason for an unpredicted ratio
The diffusion of gametes is a random process
what is it called when water diffuses through the stomata
Transpiration
What are two types of white blood cell
lymphocytes & phagocytes
What is the function of phagocytes
Engulf & digest