Pre-IB Biology Test Review

Flashcards for reviewing key concepts in Biology.

What are the two main divisions of the nervous system?

The central nervous system (CNS) and the peripheral nervous system.

How does the body respond to stimuli?

Through a pathway of nervous impulses involving different types of neurons.

What is a reflex arc?

A specific pathway of a nervous response that differs from a normal response to a stimulus.

What two components are involved in the transmission of a message across a synapse?

A synapse and a neurotransmitter.

Name three types of blood vessels

Capillaries, veins, and arteries.

Describe double circulation.

The pathway of blood through the heart involving two separate circuits.

What are the two phases of the cardiac cycle?

Diastole and systole.

What role do the AV and SA nodes play in controlling heart rate?

They are key components in the myogenic control of the heart muscle.

How does the nervous system affect heart rate?

It changes heart rate in response to specific stimuli.

What muscles are involved in the process of ventilation?

Intercostal muscles and the diaphragm.

What changes occur inside the thorax during ventilation?

Changes in pressure.

What is the role of the alveolus?

Gas exchange.

Name two types of pneumocytes found in the alveoli?

Type I and Type II pneumocytes.

Why is ventilation important for gas exchange?

Maintains concentration gradients of oxygen and carbon dioxide between the lungs and the blood.

Name three example of lipids.

Phospholipids, triglycerides, and steroids.

Are lipids polymers?

No.

What elements make up lipids

Carbon, hydrogen, and oxygen.

What molecules make up triglycerides?

One glycerol molecule and three fatty acids.

What type of reaction joins glycerol and fatty acids?

Condensation reaction.

What is the name of the reaction that breaks up a triglyceride?

Hydrolysis.

What is the difference between saturated and unsaturated fatty acids?

Their chemical structures and the presence of double bonds.

What elements are carbohydrates made of?

Carbon, hydrogen, and oxygen.

What are the three types of carbohydrates?

Monosaccharides, disaccharides, and polysaccharides.

Which carbohydrate is made up of galactose and glucose?

Lactose.

Which carbohydrate is made up of fructose and glucose?

Sucrose.

Which carbohydrate is made up of glucose and glucose?

Maltose.

Name three polysaccharides.

Glycogen, starch, and cellulose.

What is the function of glycogen?

Glucose storage in animals.

What is the function of starch?

Glucose storage in plants.

What is the function of cellulose?

Provides rigid structure in plant cell walls.

What are proteins made of?

Amino acid monomers.

What type of reaction joins amino acids together?

Condensation reactions.

How many different amino acids can be used to make proteins?

20.

What is a peptide bond?

The bond that links amino acids in a protein.

Name three functions of proteins.

Enzymes, structural components, and hormones.

Name the four levels of protein structure.

Primary, secondary, tertiary, and quaternary.

What is the primary structure of a protein?

The sequence of amino acids.

What are the two types of protein secondary structure?

Beta sheets and alpha helices.

What interactions hold together the tertiary structure of a protein?

R groups of amino acids.

When does a protein have a quaternary structure?

When it is made up of more than one polypeptide chain.

What happens when proteins denature?

They lose their specific 3D structure

Name two factors that can cause proteins to denature.

High temperatures and non-optimal pH.

What is a pathogen?

A disease-causing organism.

Name a component of the adaptive immune system.

Antibodies produced by B cells

Name the three main components of the immune system.

Barriers, the innate immune system, and the adaptive immune system.

What does the term 'biological catalysts' refer to?

Enzymes.

How do enzymes speed up reactions?

By lowering the activation energy.

What is the induced fit hypothesis?

A model explaining how enzymes specifically bind to substrates.

Name three factors that affect enzyme activity.

Temperature, pH, and substrate concentration.

How does temperature affect enzyme activity?

It affects collision frequency and can lead to heat denaturation.

How does pH affect enzyme activity?

Can result in structural denaturation of the enzyme.

How does substrate concentration affect enzyme activity?

It affects the rate of reaction until the active sites are saturated.

What is respiration?

A process that occurs in all cells to produce energy.

What is ATP?

A molecule that provides energy for cellular processes.

Where does glycolysis take place?

In the cytoplasm.

What are the products of glycolysis?

2 molecules of pyruvate, 2 ATP molecules, and NADH.

Is glycolysis part of aerobic respiration?

Yes.

Is glycolysis part of anaerobic respiration?

Yes.

What are the end products of anaerobic respiration in yeast?

Ethanol and carbon dioxide.

What is pyruvate converted to in humans during anaerobic respiration?

Lactate (lactic acid).

Where does aerobic respiration takes place?

Mitochondria.

What are the products of aerobic respiration?

Carbon dioxide, water, and ATP.

How many ATP molecules are produced in aerobic respiration?

More than 30 ATP molecules per glucose molecule.