Bio EOY

What is the function of the nucleus?

Controls the cell and contains DNA

What is the function of the cytoplasm?

Where most chemical reactions take place

What does the cell membrane do?

Controls movement of substances into and out of the cell

What is the role of mitochondria?

Site of aerobic respiration

What is the function of ribosomes?

Protein synthesis

Which structures are found only in plant cells?

Cell wall, chloroplasts, and permanent vacuole

What is the function of the cell wall?

Supports and strengthens the cell

What do chloroplasts contain?

Chlorophyll

What is the function of the vacuole?

Contains cell sap and helps maintain pressure

What is the difference between prokaryotic and eukaryotic cells?

Prokaryotic cells lack a nucleus while eukaryotic cells contain a nucleus

Why do bacteria not have a nucleus?

Their DNA is free in the cytoplasm

What are plasmids?

Small rings of DNA found in bacteria

Why are viruses not considered living?

They cannot reproduce independently

What are viruses made of?

Genetic material inside a protein coat

What must viruses infect in order to reproduce?

Living cells

What is magnification?

How many times larger the image is than the actual object

How do you calculate magnification?

Image size divided by actual size

Why should you start with the lowest magnification on a microscope?

It makes it easier to find the specimen

What does the coarse focus knob do?

Moves the stage quickly for rough focus

What does the fine focus knob do?

Sharpens the image precisely

Name three features of plants.

Multicellular, chloroplasts, cellulose cell walls

Name three features of animals.

Multicellular, no cell walls, nervous coordination

What are hyphae?

Thread-like structures in fungi

What is mycelium?

A network of hyphae

What are fungi cell walls made from?

Chitin

What does saprotrophic nutrition mean?

Feeding on dead or decaying material

Why are Protoctista difficult to classify?

Some are plant-like while others are animal-like

What are two features of bacteria?

Single-celled and prokaryotic

What is the difference between bacteria and viruses?

Bacteria are living cells while viruses are not living

Why can bacteria reproduce faster than animals?

They reproduce by rapid binary fission

What are stem cells?

Unspecialised cells that can divide and differentiate

What is differentiation?

The process where a cell becomes specialised

Where are embryonic stem cells found?

In embryos

Where are adult stem cells found?

In bone marrow and some adult tissues

Where are meristem cells found?

In growing regions of plants

Why are embryonic stem cells controversial?

Embryos are destroyed during extraction

Why are stem cells useful in medicine?

They can replace damaged cells

What is therapeutic cloning?

Creating cloned embryos for medical treatment

Why is reproductive cloning illegal in many countries?

It raises ethical and safety concerns

What diseases could stem cells potentially treat?

Paralysis, diabetes, and Parkinson’s disease

What is respiration?

The process of releasing energy from glucose

What is aerobic respiration?

Respiration using oxygen

What are the products of aerobic respiration?

Carbon dioxide and water

Why does aerobic respiration release lots of energy?

Glucose is fully broken down

What is anaerobic respiration?

Respiration without oxygen

What is produced during anaerobic respiration in animals?

Lactic acid

What is produced during anaerobic respiration in yeast?

Ethanol and carbon dioxide

Why do muscles respire anaerobically during exercise?

There is not enough oxygen available

What causes muscle fatigue during anaerobic respiration?

Build-up of lactic acid

Which type of respiration requires oxygen?

Aerobic respiration

What is diffusion?

Movement of particles from high concentration to low concentration

What direction does diffusion occur in?

Down a concentration gradient

Give one example of diffusion in the body.

Oxygen moving from alveoli into blood

What is osmosis?

Movement of water through a partially permeable membrane

What type of membrane is needed for osmosis?

A partially permeable membrane

What happens to a plant cell in a dilute solution?

It becomes turgid

What happens to a plant cell in a concentrated solution?

It becomes plasmolysed

Why does osmosis not occur without water?

Osmosis only involves water molecules

What is active transport?

Movement of substances against the concentration gradient using energy

How is active transport different from diffusion?

It requires energy and moves against the gradient

Which reagent is used to test for glucose?

Benedict’s solution

What colour change shows a positive glucose test?

Blue to brick red

Why must Benedict’s test be heated?

Heat is needed for the reaction

Which reagent is used to test for starch?

Iodine solution

What colour shows a positive starch test?

Blue-black

Which reagent is used to test for protein?

Biuret solution

What colour shows a positive Biuret test?

Purple

How is the emulsion test carried out?

Add ethanol then water to the sample

What result shows fats are present?

A cloudy white emulsion

Why are controls important in experiments?

They make results reliable for comparison

Why do humans need carbohydrates?

For energy

Why do humans need proteins?

For growth and repair

Why are fats important in the diet?

For insulation and energy storage

Why do humans need vitamins?

To keep the body healthy

Why is fibre important?

Helps food move through the digestive system

Why is water essential?

Needed for chemical reactions and transport

What can happen if someone has an unbalanced diet?

Malnutrition or deficiency diseases

How does the burning biscuit test work?

Food is burned to heat water and measure energy transfer

Why is the bomb calorimeter more accurate?

Less heat energy is lost

What is energy in food measured in?

Kilojoules or kilocalories

What is physical digestion?

Breaking food into smaller pieces

What is chemical digestion?

Breaking down molecules using enzymes

What happens in the mouth during digestion?

Food is chewed and mixed with saliva

What is the function of saliva?

Contains amylase to digest starch

What does the oesophagus do?

Moves food to the stomach

What happens in the stomach?

Food is churned and proteins are digested

What is the function of hydrochloric acid in the stomach?

Kills bacteria and provides optimum pH for enzymes

What does the liver produce?

Bile

What is the function of the gall bladder?

Stores bile

What does the pancreas produce?

Digestive enzymes

What happens in the small intestine?

Digestion and absorption occur