Topic 2 Using Spec

Question 1

Describe cancer as the result of changes in cells that lead to uncontrolled cell division

Answer 1

When the cell goes through a mutation it can lead to uncontrolled cell division and new cells are produced even when the body does not need them. A group of cancerous cells produce a growth called a tumour

Question 2

What is the zone of elongation

Answer 2

Further up the root and its where new cells grow in size

Question 3

What is the zone of differentiation

Answer 3

Even further up the root and where new cells differentiate

Question 4

Cell differentiation in plants

Answer 4

Many plants keep their ability to differentiate throughout their life therefore plants are always able to create new tissues

Question 5

Differentiation in animals

Answer 5

Cell differentiation is rare in mature animals
Their cells mostly divide in order to replace cells and repaired tissues
New tissues are rarely created

Question 6

What are plant stem cells

Answer 6

Found in the meristem tissue and can differentiate into all type of plant cell throughout the life of the plant. This allows plants to grow for their whole lives

Question 7

What do stem cells in embryos do

Answer 7

Differentiate into most cell types to produce all the cell types that will make up the organism

Question 8

What does a percentile chart show and how

Answer 8

Whether the baby is growing as they should be
The baby’s age (x-axis) and weight (y-axis)
If a baby is in the 1st percentile, 99% of all other babies at that age are heavier.

Question 9

What can stem cells be used to do

Answer 9

Replace damaged cells that cause diabetes

Question 10

What is therapeutic cloning

Answer 10

a process that produces (creates) an embryo with the same genes as the patient.
Stem cells taken from this embryo will have the same DNA as the patient. This means that the patient’s body will not reject the stem cells or body cells made from the embryo’s stem cells.

Question 11

What are some disadvantages of using stem cells in medical treatment

Answer 11

.Stem cell transplantation could transfer viral infections
.ethical beliefs - killing an embryo is bad
. Rejection - introducing stem cells into a patient could cause the patient’s immune system to reject and destroy the new cells.

Question 12

What is the brains function

Answer 12

The brain is made up of millions of interconnecting neurones (nerve cells).
Different regions of the brain are responsible for coordinating (organising) different functions.

Question 13

Why is it hard to treat brain problems

Answer 13

As the brain is only partially understood

Question 14

What is the function of the cerebellum

Answer 14

Responsible for muscle coordination and is important for movement, posture, balance and speech

Question 15

What is the function of the medulla oblongata

Answer 15

Responsible for unconscious activities such as breathing and heartbeat

Question 16

What is the function of the cerebral hemispheres

Answer 16

responsible for conscious thought (e.g. memory, language and intelligence).

Question 17

How can we overcome the difficulties of of accessing brain tissue inside the skull

Answer 17

With the use of CT scanning and PET scans

Question 18

How do CT scanners show the brains functions and identify tumours

Answer 18

Lots of x-rays are taken of the brain, and a computer then builds a 3D image of the brain’s structure.
Different types of cells absorb different amounts of the x-rays.
Brain tumours show up as white blotches.

Question 19

How do PET scanners investigate brain functions

Answer 19

Using radioactive glucose, the amount of glucose different parts of the brain are using up can be detected.
An image of brain activity is then made.

Question 20

Limitations of treating brain tumours

Answer 20

Treated with chemotherapy, radiotherapy or Brain surgery however these also cause lots of damage to the body

Question 21

Limitations of spinal injury

Answer 21

If the spinal cord is severed (cut), electrical impulses can no longer travel to the brain.
Wires can partly re-connect the spinal cord, but this isn’t very effective.

Question 22

What do neurones do

Answer 22

Carry electrical impulses between receptors

Question 23

What is a synapse

Answer 23

Gaps between neurones

Question 24

Describe synapses in the transmission of electrical impulses

Answer 24

The electrical impulse reaches the end of the neurone before the synapse.
This triggers the release of chemicals called neurotransmitters.
The neurotransmitters diffuse (move down a concentration gradient) across the synapse.
The neurotransmitters bind to receptors on the next neurone.
The presence of the neurotransmitter causes the production of an electrical impulse in the next neurone

Question 25

Describe the function of axons based on the neurone structure

Answer 25

They carry electrical impulses away from the cell body

Question 26

Describe the function of dendrites based on neurone structure

Answer 26

Carry electrical impulses towards the cell body

Question 27

What is a structural benefit for the axons

Answer 27

They are covered in a layer of myelin sheath which insulates the neurone so electrical impulses travel down it more quickly

Question 28

How does the CNS respond to stimuli

Answer 28

Via a reflex arc

Question 29

What are stimulus detected by

Answer 29

A receptor

Question 30

What is the function of receptors

Answer 30

They detect change in the environment and initiate a signalling process within the body
The signal is then picked up by a neurone

Question 31

What are the three types of neurones

Answer 31

Sensory neurones
Relay neurones
Motor neurones

Question 32

What does the sensory neurone do

Answer 32

Carries the signal in the form of an electrical impulse to the CNS

Question 33

What does the relay neurone do

Answer 33

Relays the electrical impulse from sensory to the appropriate motor neurone

Question 34

What does the motor neurone do

Answer 34

Carries the electrical impulse from the CNS to an effector

Question 35

Practical for amylase and ph

Answer 35

Add start the iodine solution will be blue/black as there’s loads of starch
Add amylase to break down starch in the test tube
Every 30 seconds get pipette and drop amalyse and starch solution
Add iodine to every spotting role

Question 36

Why Does the colour not change

Answer 36

The amaylse denatures and active site changes shape