Unit 2 Flashcards
What are tissues
A group of similar cells that work together for a particular function
What are organs
A structure made of a group of tissues working together to perfoerm a function
Name 3 facts about stem cells
They are in specialized cells in animals
They can divide and become specialized cells by variation
Stem cells are needed for growth and repair
Name the 10 places you can find stem cells
Brain, blood vessels, skeletal muscle, peripheral blood, bone marrow, teeth, skin, heart, liver, gut
What are meristems
Sites of cell division in plants
Eg root and shoot tips
What can unspecified meristems do
Grow into specialized plant cells eg xylem
Name the three parts of the central nervous system
Brain
Spinal cord
Nerve cells
Name the three parts of the brain
cerebrum, cerebellum, medulla
State the function of the cerebrum
Controls memory, personality and conscious thought
State the function of cerebellum
Controls balance and coordination
State the function of the medulla
Controls heart rate and breathing rate
What’s is a reflex arc
The sequence of neurons a nervous impulse passes through to cause a reflex action
What is the order of neurons In a reflex arc?
Sensory, relay, motor
What is a reflex action
A rapid automatic response to a stimulus
What’s the sequence in reflex action
Sense receptor, sensory neuron, relay neuron, motor neuron, effector(muscle)
What is a synapse and what happens
A gap between two neurons
Signals are passed across this junction by chemical messengers called neortansmitters
How do signals travel along nerves
By electrical impulses
Name three facts about hormones
Chemical messengers
Made by endocrine glands
Transported around the body by the blood
Which 6 places in e body do you find endocrine glands
Testis, ovary, pancreas, adrenal, thyroid, pituitary
Why is glucose needed
To make ATP
What controls levels of glucose in the blood
Hormones insulin and glucagon
When is glucagon produced
When glucose is gone
When controlling glucose levels in high blood pressure, what are the 4 stages
Too much glucose in blood
pancreas produces more insulin
Increase glucose uptake by cells and glycogen formation
Blood glucose levels decrease
When controlling glucose levels in low blood pressure, what are the 4 stages
Too little glucose in blood
Pancreas,produces more glucagon
Breakdown of glycogen in liver
Blood glucose levels increase
What are all sex cells known as
Gametes