Animal Physiology Quiz

Amylase is an enzyme that breaks down complex carbohydrates like glycogen into simpler sugars. Maltose and branched oligosaccharides are intermediate products in this breakdown process.

Supercooling involves lowering the body temperature below the freezing point of water without forming ice crystals. Controlled ice formation allows animals to form ice crystals in specific locations outside of their cells, which reduces the risk of damage to internal tissues.

Brown adipose tissue (BAT) is a specialized type of fat tissue that generates heat. It does this by uncoupling the electron transport chain in mitochondria, which means that less ATP is produced and more energy is released as heat.

Ectotherms rely on external sources of heat to regulate their body temperature. Exposure to intense lighting can increase the metabolic rate in ectotherms because it provides a source of external heat.

Disaccharides are sugar molecules composed of two monosaccharides. Salivary amylase can break down some disaccharides, but most are broken down by enzymes in the small intestine.

Poikilotherms are animals whose body temperature fluctuates with the environment. They do not have a thermoneutral zone – a range of temperatures where their metabolic rate is minimized.

The citric acid cycle and beta oxidation of fatty acids are important metabolic processes, but they occur in the mitochondria, not the cytoplasm.

Quantitative thermal acclimation involves changes in the number or amount of specific molecules or structures in the cell or tissue. For example, a fish acclimated to cold temperature (5°C) might have a higher density of mitochondria to support its metabolic needs.

Larger animals tend to have a greater volume compared to their surface area. This means they lose heat at a slower rate, making them better suited for colder climates.

Some animals can enter a state of reduced metabolic activity and lowered body temperature, called torpor, to conserve energy during periods of food scarcity or cold temperatures.

The evolution of endothermy, the ability to maintain a stable internal temperature, can be attributed to various factors such as parental care and increased aerobic capacity. These factors are not mutually exclusive, meaning they can all contribute to the development of endothermy.

Volume-based processes, like heat production, increase faster with size than surface-based processes, like heat dissipation. So, larger animals produce more heat but lose it at a slower rate.

Justus von Liebig, a German chemist, is credited with the concept of the 'Law of the Minimum', which states that the growth of a plant is limited by the nutrient that is most scarce, even if other nutrients are abundant.

Allometric scaling describes the non-linear relationship between an animal's size and its metabolic rate. This means that metabolic rate doesn't increase proportionally with body size, it follows a power law.

Invertebrates, though lacking internal temperature regulation, can use behavioral mechanisms like basking in the sun or seeking shade to control their body temperature.

Multicellularity, the ability of organisms to have many cells working together, relies on cell differentiation. This means cells specialize for different functions, allowing complex organisms to develop.

Claude Bernard's concept of 'the internal milieu' refers to the stable internal environment that organisms must maintain to function properly. This is a key precursor to the idea of homeostasis.

Endotherms, animals that maintain a stable internal temperature through metabolic processes, have higher metabolic rates than ectotherms of the same size. This is because they need more energy to generate and regulate heat.

All living organisms, including animals, continuously use chemical energy to maintain order within their cells, combating the natural tendency towards increasing disorder (entropy).

Muscles contracting to lift an object involve mechanical energy to move the object, while DNA synthesis stores chemical energy in molecular bonds.

Enzymes act as catalysts, speeding up reactions. A single molecule of cAMP-dependent protein kinase can activate many glycogen phosphorylase kinase molecules, which in turn activate many glycogen phosphorylase molecules. This cascading effect allows for efficient breakdown of many glycogen molecules.

The difference in height between children raised in different environments can be explained by environmental factors, not natural selection. Natural selection acts on genetic changes over generations, not within an individual's lifetime.

Enzymes bind to their substrates non-covalently, meaning they do not form permanent bonds. This interaction involves a change in the enzyme's shape (conformation) to facilitate the reaction.

Allosteric modulators, like AMP, can bind to enzymes at a site distinct from the active site, causing a conformational change. This change alters the enzyme's activity, in this case increasing phosphofructokinase's activity.

The Km value represents the substrate concentration at half the maximum reaction velocity. The curve with the lowest Km value reaches half its maximum velocity at a lower substrate concentration.

G-protein coupled receptors (GPCRs) are characterized by their ability to activate intracellular signaling pathways through G-proteins, which bind to guanine nucleotides like GDP.

Gap junctions allow small molecules and ions to pass directly between cells, while occluding junctions (tight junctions) form a tight seal between cells, preventing paracellular movement.

Metabolic rate is the energy expenditure per unit time. Calculate the total energy output and divide by the time period to obtain the average metabolic rate.

ATP synthase utilizes the electrochemical gradient of hydrogen protons across the mitochondrial membrane to drive the synthesis of ATP. This gradient is created by electron transport, but not directly from ATP breakdown.

Phosphagen systems provide rapid ATP supply but are limited because they rely on pre-formed stores of high-energy compounds. They can't be sustained as a primary source.

The Krogh Principle states that any given biological problem can be most easily studied using an appropriate organism, acknowledging the diversity of biological systems.

Many metazoans have the capacity for both asexual and sexual reproduction, despite the fact that some species reproduce only asexually.

The evolution of multicellularity is a complex process influenced by various selective pressures, not mutually exclusive hypotheses.