biology current chapters 1

ch 16, 5, 6, 7

What are the two main types of prokaryotes?

Bacteria and Archaea

What distinguishes Archaea from Bacteria?

Archaea have different molecular genetic profiles.

What is the structure of a bacterial cell wall made of?

Peptidoglycans

What type of DNA do prokaryotes have?

Circular DNA molecule

What are the three common shapes of bacteria?

Bacillus, coccus, and spirillum

How do bacteria reproduce?

Through binary fission, which is a form of asexual reproduction.

What are resistant endospores?

Dormant structures that can survive harsh conditions and germinate when conditions are normal.

What is conjugation in bacteria?

The transfer of DNA to other bacterial cells using a sex pilus.

What is the significance of Gram staining?

It is a method used to identify bacteria based on their cell wall composition.

Name a common disease caused by Streptococcus bacteria.

Streptococcus pneumoniae causes bacterial pneumonia.

What is the primary cause of tuberculosis?

Mycobacterium tuberculosis, which usually infects the lungs.

What are two bacteria that cause food poisoning?

Salmonella and Listeria

How do antibiotics work against bacterial infections?

They interfere with metabolic pathways, such as inhibiting protein synthesis or cell wall synthesis.

What are some problems associated with antibiotic therapy?

Allergic reactions, loss of beneficial bacteria, and bacterial resistance.

What role do prokaryotes play in nitrogen fixation?

They convert nitrogen gas to liquid ammonia for use by plants.

What is ATP and its role in cellular metabolism?

Adenosine triphosphate is the energy currency of the cell, providing energy for cellular reactions.

What is the difference between endergonic and exergonic reactions?

Endergonic reactions require energy input, while exergonic reactions release energy.

What is the function of enzymes in biochemical reactions?

Enzymes act as catalysts to speed up reactions without being consumed.

How do enzymes lower the activation energy of reactions?

They bring reactants together and change shape when complexed with substrates.

What is negative feedback in enzymatic action?

A regulatory mechanism where the product of a reaction inhibits its own production.

What is simple diffusion?

The movement of molecules from a higher to a lower concentration without energy input.

What is osmosis?

The diffusion of water across a selectively permeable membrane.

What is endocytosis?

A process where the cell membrane engulfs molecules to bring them into the cell.

What is exocytosis?

A process where vesicles fuse with the cell membrane to release molecules outside the cell.

Cellular Respiration

Breakdown of glucose releases energy; coupled to ATP synthesis.

Aerobic Process

A process that requires O2 and releases CO2.

Glycolysis

Breakdown of one glucose (6 carbons) to two smaller molecules (3 carbons each) in cytoplasm.

ATP

A molecule that stores energy for cellular processes.

Krebs Cycle

A cycle where 2-carbon enters and produces ATP and CO2.

Electron Transport Chain

A series of electron carrier proteins in the cristae that pass electrons and produce ATP.

NADH

A coenzyme that carries electrons during cellular respiration.

FADH2 (“Flavin adenine dinucleotide“)

A coenzyme that carries electrons during the Krebs cycle.

Cristae

The large surface area of the inner mitochondrial membrane that produces large amounts of ATP.

Pyruvate

A 3-carbon molecule that is converted to acetyl-CoA (“acetyl-Coenzme A“) in the transition step.

Acetyl-CoA

A 2-carbon molecule formed from pyruvate before entering the Krebs cycle.

Photosynthesis

The process by which solar energy is converted into chemical energy.

Autotrophic

Organisms that provide food for heterotrophs.

Chlorophyll

A pigment that captures sunlight for photosynthesis.

In what process are Light Reactions present?

Converting solar energy to chemical energy, producing ATP and NADPH.

NADPH

A coenzyme that carries pairs of energized electrons from chlorophyll.

Carbon Reactions

Light-independent reactions where CO2 is converted to glucose.

Thylakoid Membrane

The membrane where protons move through ATP synthase to generate ATP.

Proton Gradient

A difference in proton concentration across a membrane that drives ATP synthesis.

What process requires Oxygen Byproduct?

Oxygen released during the light reactions of photosynthesis.

Glucose

A carbohydrate produced from CO2 in the carbon reactions of photosynthesis.

Energy Transfer

The movement of energy from one form to another, such as from sunlight to chemical energy.