Topic 2

Mitosis

Asexual process where two identical diploid data cells are produced

What are the stages of the cell cycle?

Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Cell cycle

The process that include Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis that produces 2 identical diploid daughter cells

What are the stages of the mitosis?

Prophase, Metaphase, Anaphase, Telophase

What is the first stage of the cell cycle?

Interphase

What is the second stage of the cell cycle?

Prophase

What is the third stage of the cell cycle?

Metaphase

What is the fourth stage of the cell cycle?

Anaphase

What is the fifth stage of the cell cycle?

Telophase

What is the final stage of the cell cycle?

Cytokinesis

What is the first stage of mitosis?

Prophase

What is the second stage of mitosis?

Metaphase

What is the third stage of mitosis?

Anaphase

What is the final stage of mitosis?

Telophase

Does mitosis begin with a diploid or haploid cell?

Diploid

What happens in interphase?

• DNA replication

• Protein synthesis

• Chromosomes form x shapes (2 armed)

What happens in prophase?

• Nucleus begins to break down

• Spindle fibres appear

• Chromosomes thicken/condense

What happens in metaphase?

Chromosomes lineup along the equator/ middle of the cell

What happens in anaphase?

Chromosomes pull apart and move away to either end of the cell

What happens in telophase?

Nuclei form at either the end of the cell

What happens in cytokinesis?

2 genetically identical diploid daughter cells are produced

Does mitosis produce diploid or haploid cells?

Diploid

Does mitosis produce genetically different or identical cells?

Genetically identical

How do you calculate mitotic index?

Number of cells in mitosis / total number of cells

Binary fission

A type of asexual reproduction used by bacteria

Cancer

Disease caused by uncontrolled cell division by mitosis

Tumour

A lump formed of cancer cells

What does uncontrolled cell division cause?

Tumours

Name 2 types of tumours

Benign and Malignant

Do benign tumours usually grow slowly or quickly?

Slowly

Do malignant tumours usually grow slowly or quickly?

Quickly

Are benign tumours cancerous?

No

Are malignant tumours cancerous?

Yes

Are benign tumours usually easy to remove?

Yes

Are malignant tumours usually easy to remove?

No

What type of tumour doesn’t invade the parts of the body?

Benign

Do benign tumours spread?

No

Do malignant tumours spread?

Yes

Explain the process of malignant cells spreading

• Cells secrete chemicals

• Stimulate blood vessels to grow

• Cells detach

• Spread via blood

• Form new tumors called secondary tumors

Differentiation

When unspecialised cells like stem cells become specialised

Undifferentiated

Unspecialised cells that don’t have a function

Stem cells

Undifferentiated cells that differentiate into specialised cells

Embryonic stem cells

Undifferentiated cells in an early embryo that differentiate into any type of specialised cells

Adult stem cells

Undifferentiated cells in an early embryo that differentiate into any type of specialised cells

Are stem cells undifferentiated or differentiated?

Undifferentiated

Are specialised cells undifferentiated or differentiated?

Differentiated

Do stem cells have a function?

No

What can stem cells differentiate into?

Specialised cells like heart muscle cells, red blood cells, nerve cells

What do stem cells replace?

Replace damaged cells

What do stem cells repair?

Repair damaged tissue

Where are adult stem cells found?

Bone marrow

What can adult stem cells differentiate into?

Only major tissues/organ cells

What can embryonic stem cells differentiate into?

Any specialised cell

What are the benefits of using stem cells for medicine?

• Used to treat currently untreatable conditions

• Used to grow organs for transplants

• Used for medical research

What are the risks of using stem cells for medicine?

• Rejection

• Ethical issues around use of embryonic stem cells

• Could be contaminated with pathogens

• Stem cells divide quickly which could lead to cancer

Where does cell division in plants occur?

Meristem

Meristem

An area of undifferentiated cells in a plant where cells are dividing rapidly by mitosis

What is another name for the meristem?

Zone of cell division

What occurs in the zone of elongation?

Cells increase in length and contribute to plant growth

What occurs in zone of differentiation?

Stem cells differentiate into specialised cells

What does CNS stand for?

Central Nervous System

Stimuli

A thing or event that leads to a reaction

What do receptors detect?

Stimuli

Where are the 5 receptors in the body?

Eyes, skin, ears, nose, tongue.

What stimuli do the eyes detect?

Light and color

What stimuli do the ears detect?

Sound and vibrations

What stimuli does the skin detect?

Pressure and pain

What stimuli do the tongue detect?

Chemicals in food

What stimuli does the nose detect?

Chemicals in the air

Name the 3 types of neurone in order

Sensory, relay and motor

What is the first neurone in the nervous system?

Sensory neurone

What is the last neurone in the nervous system?

Motor neurone

Describe the structure of sensory neurone

• Dendrites

• Dendron

• Cell body with nucelus

• Axon

• Axon terminals

• Myelin sheath

Describe the structure of relay neurone

• Dendrites

• Cell body with nucleus

• Axon

• Axon terminals

Describe the structure of motor neurone

• Dendrites

• Cell body with nucleus

• Axon

• Axon terminals

• Myelin sheath

What structures do all 3 neurones have?

• Dendrites

• Cell body with nucleus

• Axon

• Axon terminals

Which neurones have a myelin sheath?

Sensory and motor neurone

Which neurones have a dendron?

Sensory neurone

Which neurone is connected to the effector?

Motor neurone

Effector

Muscle/gland

Myelin sheath

Fatty layer that insulate the neurone. This speeds up the electrical impulses transmission so less impulse is lost to the surroundings.

Does myelin sheath protect or insulate the neurone?

Insulate

Does the myelin sheath speed up or slow down the electrical impulse transmission?

Speed up

What is a gap between 2 neurones?

Synapse

Synapse

A gap between 2 neurones; connects the neurones

What happens in the synapse between neurones?

• The impulse reaches the axon terminals

• A neurotransmitter diffuses across the gap

• Next neurone detects this

• New impulse is generates

Explain the process of the electrical impulse across the CNS

• Receptors detect stimuli

• Information converts into an electrical impulse

• Impulse travels along sensory neurone, synapse, relay neurone, synapse, motor neurone and then the effector

• This generates a response

Name the different parts of the brain

Cerebral cortex, spinal cord, cerebellum and medulla oblongata

What is the largest part of the brain?

Cerebral cortex

What side of the body does the right side of the cerebral cortex control?

Left

What side of the body does the left side of the cerebral cortex control?

Right

What do different parts of the cerebral cortex control?

Different things like language, vision, smell , personality, movement etc.

What is the cerebral cortex split into?

2 hemispheres

Cerebral cortex

• The largest part of the brain that’s split into 2 hemispheres

• Different parts are responsible for different things like speech, vision, movement, language, personality etc.

• Right side controls left side of the body

• Left side controls right side of the body

What is the cerebellum responsible for?

Balance, posture, fine muscle activity

What is the medulla oblongata responsible for?

Controls heart rate, breathing, automatic/unconscious responses, reflexes for vomiting + sneezing

Spinal cord

A bundle of neurones that carries electrical impulses around the body. It relays information form the brain to the rest pf the body.

What part of the brain controls language, speech, movement, vision, smell, personality etc.?

Cerebral cortex

What part of the brain controls fine muscle activity, balance and posture?

Cerebellum

What part of the brain controls automatic/unconscious responses like heart rate, breathing and reflexes for vomiting + sneezing?

Medulla oblongata