Explanation:
Cholesterol (Choice C) is a non-polar hydrophobic molecule. Therefore, it is insoluble in water.
Glucose (Choice A), amino acids (Choice B), and sodium chloride (Choice D) are soluble in water and are hydrophilic.

Explanation​:
Water's thermal properties (Choice A) include a high heat of vaporisation which results in the absorption of a large amount of heat by water before changing its physical state. This means that changing the temperature of the water is slow, and this helps to maintain the internal temperature of organisms between set limits.
Water has cohesive properties (Choice B) which means it sticks to other water molecules.
Water has adhesive properties (Choice C) which means it adheres to charged surfaces.
Water is an excellent solvent (Choice D) which means it dissolves a wide array of polar and ionic substances.

Explanation​:
DNA molecules consist of four nitrogenous bases: adenine (A), cytosine (C), guanine (G) and thymine (T). In DNA molecules, adenine always pairs with thymine and cytosine always pairs with guanine. This is known as complementary base pairing.

Sequences I and III both follow base-pairing rules correctly. Statement II is incorrect because it shows T paired with G and A paired with C.

Explanation​:
Hydrophilic (Choice C) substances dissolve in water through the formation of hydrogen bonds with water.
Non-polar (Choice D) substances are not attracted to water molecules and do not form bonds with them. These substances are hydrophobic (Choice B), making them insoluble (Choice A) in water.

Explanation:
A group of individuals living in a defined area is not a biological definition (Choice A). A group of individuals of the same species living in a given area at the same time who are interacting with each other is a population (Choice B) and the environment in which they live is a habitat (Choice C). It is only when they can interbreed to produce fertile offspring that they can be considered a species. (Choice D).

Explanation:
Eukaryotic cells contain mitochondria but prokaryotic cells do not. Choice A is correct.

Choices B and D are incorrect as the cell is not prokaryotic; it has a nucleus. Choice C is incorrect because the cell has a nucleus.

Explanation:
Choice A is correct because statements I and II are common features of bacterial cells. Archaeans, which are prokaryotes, have DNA associated with histone proteins, but bacteria do not (statement III).

Explanation:
The chromosomes of eukaryotes are linear, and the DNA is coiled around histone proteins (Choice C). Choice A is incorrect because eukaryotic DNA molecules are not circular. Choice B is incorrect because eukaryotic cells do not have looped DNA in the nucleus. Choice D is incorrect because the linear DNA molecules in eukaryotic cells are coiled around histone proteins.

Explanation​:
In water, a hydrogen bond (Choice B) is formed between partially the positively charged hydrogens of one water molecule and the partially negatively charged oxygens on another water molecule. Choice A is incorrect because this bond is intramolecular. Choices C and D are incorrect because water does not form ionic or metallic bonds with itself.

Explanation​:
Statement I is true because all cells have cytoplasm enclosed by the plasma membrane.

Statement II is also true because the invention of the microscope made viewing structures within the cell easier.

Statement III is false because all cells have genetic material. Eukaryotic cells have their genetic material inside of the nucleus, while prokaryotes have their genetic material in the nucleoid region.

Explanation​:
Choice A - Chlorella is capable of photosynthesis which makes it an autotroph. The main photosynthetic pigment is chlorophyll. Therefore, Chlorella produces its own carbohydrates for nutrition.

Choice B - Chlorella reproduces asexually through cell division.

Choice C - Chlorella reacts to different factors in the environment such as light, nutrients, and carbon dioxide. As each of these variables changes, Chlorella responds in various ways.

Choice D - Chlorella releases oxygen as a product of photosynthesis.

Explanation​:
Organelles of a eukaryotic cell are enclosed by a single or double membrane. Double membrane-bound organelles include the nucleus, mitochondria, and chloroplasts. So, a mitochondrion has a double membrane.

The Golgi apparatus (Choice A), lysosome (Choice C), and endoplasmic reticulum (Choice D) all have a single membrane.

Choice A is incorrect as eukaryotes (as well as Archae) contain 80S ribosomes. Choice B is incorrect as both eukaryotic and prokaryotic cells contain a plasma membrane. Choice C is incorrect as eukaryotic cells contain a nucleus but prokaryotic cells do not.

Explanation​:
Choices A, B and D are incorrect as they all have a single membrane.

Explanation:
Choice A - Excretion is the process wherein waste and excess water in the organism are removed. Paramecia expel waste products such as carbon dioxide through the process of diffusion.

Choice B - Homeostasis pertains to the ability of living things to maintain a stable internal environment. Paramecia maintain a stable internal condition by expelling excess water using the contractile vacuole.

Choice C - Reproduction is the biological process by which organisms produce offspring that are biologically similar to themselves. Paramecia can reproduce sexually through meiosis and asexually through mitosis.

Choice D - Metabolism refers to all the chemical reactions in organisms such as anabolic and catabolic reactions. Paramecia produce enzymes that catalyse different catabolic and anabolic reactions in the cell.

Explanation:
The resolution is the ability to distinguish between two objects. Choice B is correct.

Choices A and D are incorrect because a photograph taken using an electron microscope would allow the ultrastructure of the cells (fine detail of cells, such as organelles) to be observed. Choice C is incorrect because these photographs are magnified at the same power.

Explanation:
All 64 codons of the genetic code are present in all organisms, apart from minor variations indicating that all life evolved from the same original cells (Choice D).

Eukaryotic cells evolved from prokaryotic cells (Choice A) is incorrect as this is the endosymbiotic theory. Choice B is incorrect as mitochondria do not have a cell wall. Choice C is incorrect as bacteria do not have histones.

Explanation:
Bound ribosomes synthesise proteins for secretion outside of the cell, membrane-associated proteins or proteins used in lysosomes (Choice D).

Choice A is incorrect, as free ribosomes synthesise proteins for use primarily within the cytoplasm.
Choice B is incorrect as bound ribosomes do not transport mRNA from the nucleus to the cytoplasm.

Explanation:
Adhesive properties (Choice B) refer to water’s ability to stick to charged surfaces or polar molecules. This, together with cohesion, allows water to move against gravity up the stem through capillary action.

Water's melting point (Choice A) is the temperature at which it changes its state from solid to liquid.

The specific heat capacity (Choice C) of water pertains to the amount of heat energy needed to raise its temperature by 1 °C.

The buoyant force of water (Choice D) is the upward force on an object submerged or partially immersed in water, equal to the weight of the displaced water.

Explanation​:
Choice D is correct because water has a relatively high density compared to many substances which increases the buoyancy forces it exerts on objects submerged in it.

Choice B is incorrect because specific heat capacity refers to how much energy is required to raise the temperature of a unit of mass of a given substance by one degree Celsius. Choice C is incorrect because viscosity refers to the resistance of a fluid to an object moving through it or to flow of the fluid itself.

Explanation​:

Urbanisation is not decreasing, it is increasing all over the world, which is contributing to the current biodiversity crisis. Choice A is correct.

The widespread use of vaccines has led to fewer people dying of diseases before reproductive age, contributing to worldwide population growth, which contributes to the current biodiversity crisis, so Choice B is incorrect. Increased air travel results in more pollution and makes it easier for diseases to spread worldwide which sometimes negatively impacts species, contributing to the biodiversity crisis, so Choices C and D are incorrect.

Explanation:

Rewilding projects attempt to restore and rehabilitate ecosystems by reintroducing native species and allowing natural processes to become re-established. Statement I is therefore correct. Recycling and reusing products means fewer resources will be extracted from the Earth which is a process that can destroy natural habitats and lead to excessive landfill use, so Statement II is correct. Choice C is therefore correct (Statement I and II).

Increasing meat consumption (Statement III) results in more land being cleared for animals such as cattle to be bred, decreasing biodiversity. Choice D is therefore incorrect as it includes this statement. Choices A and B are missing one of the possible solutions to the crisis and are therefore incorrect.

Explanation​:
The number of organisms found via the fossil record for any era is much lower compared to the number of organisms found on Earth now and those that continue to be found, so Choice B is correct. Choice A is incorrect as changing levels of atmospheric carbon dioxide provide evidence for humans' impact on carbon dioxide levels. Choices C and D are incorrect as evidence suggests that the rate of evolution and speciation are increasing, which provides evidence for increasing biodiversity.