Question

Match each term with its most suitable description. __reactant __phagocytosis __first law of thermodynamics __product __cofactor __concentration gradient __passive transport __active transport a. assists enzymes b. forms at reaction's end c. enters a reaction d. requires energy input e. one cell engulfs another f. energy cannot be created or destroyed \(\mathrm{g}\). basis of diffusion h. no energy input required

Short answer

Reactant: c, Phagocytosis: e, First law of thermodynamics: f, Product: b, Cofactor: a, Concentration gradient: g, Passive transport: h, Active transport: d.

Step-by-step solution

Match 'reactant'

The term 'reactant' refers to substances that enter a chemical reaction to be transformed into products. Therefore, the best description for 'reactant' is c: enters a reaction.

Match 'phagocytosis'

Phagocytosis is a process where one cell engulfs another cell or particle. Therefore, the best description for 'phagocytosis' is e: one cell engulfs another.

Match 'first law of thermodynamics'

The first law of thermodynamics states that energy cannot be created or destroyed, only transformed. Therefore, the best description is f: energy cannot be created or destroyed.

Match 'product'

A 'product' is the substance formed at the end of a chemical reaction. Therefore, the best description is b: forms at reaction's end.

Match 'cofactor'

A 'cofactor' is a chemical compound that helps enzymes perform their function. Therefore, the best description is a: assists enzymes.

Match 'concentration gradient'

A 'concentration gradient' showcases the basis of diffusion, where substances move from an area of higher concentration to an area of lower concentration. Therefore, the best description is g: basis of diffusion.

Match 'passive transport'

'Passive transport' refers to the movement of substances across a cell membrane without the need for energy. Therefore, the best description is h: no energy input required.

Match 'active transport'

'Active transport' is the movement of substances across a membrane requiring energy, usually against a concentration gradient. Therefore, the best description is d: requires energy input.

Key concepts

Chemical Reactions

Chemical reactions are essential processes that modify the structure or composition of molecules. When you hear the term 'reactant,' it refers to the starting substances in a chemical reaction, consumed to form new products.
Reactants participate in different types of reactions such as synthesis, decomposition, replacement, and combustion. By transforming reactants, chemical reactions create 'products,' which are the resultant substances.
Think of reactants as ingredients you put into a recipe, and the products as the finished dish. This transformation is orchestrated under specific conditions, which can include factors like temperature and pressure. Chemical reactions often release or absorb energy, and they are pivotal in everyday processes such as digestion, respiration, and photosynthesis.

Cell Processes

Cell processes ensure the proper functioning of living organisms by maintaining homeostasis and performing necessary metabolic activities. One important cell process is phagocytosis, where a cell eats or engulfs another cell or particle to absorb nutrients or remove pathogens.
This process is part of a larger group of processes known as endocytosis, which also includes pinocytosis (cell drinking) and receptor-mediated endocytosis.
Understanding these cell processes gives insight into how cells maintain their environment, obtain nutrients, and deal with unwanted substances or pathogens they encounter. Essentially, each cell process contributes to the survival, growth, and reproduction of cells, allowing them to carry out their functions effectively.

Thermodynamics

Thermodynamics is the study of energy transformations, especially how energy is conserved in physical and chemical processes.
The first law of thermodynamics, also known as the law of energy conservation, states that energy cannot be created or destroyed. This fundamental principle implies that the total amount of energy in an isolated system remains constant, though it can change forms.
For example, when food is consumed, it is metabolized by the body to release energy for activities, with energy storage and heat as by-products. Understanding thermodynamics is crucial in fields like chemistry and physics, aiding in the explanation of how reactions occur and how they can be harnessed for work.

Enzyme Function

Enzymes are biological catalysts crucial for speeding up biochemical reactions without being consumed in the process. They rely on helpers known as cofactors, which are usually minerals or vitamins, to function optimally.
Cofactors assist enzymes by stabilizing the transition state of a reaction, binding to the enzyme to form active sites, or aiding in the transfer of groups between molecules.
Typically, without adequate cofactors, enzyme activity decreases, often leading to metabolic imbalances. Understanding enzyme function and the role of cofactors can help in the development of pharmaceuticals and in the diagnosis of metabolic diseases.

Cell Transport

Cell transport mechanisms are vital for moving substances across cell membranes, allowing cells to maintain a stable environment.
There are two main types of transport: passive and active transport.

• Passive Transport: This process moves substances down their concentration gradient without energy input. Examples include diffusion, osmosis, and facilitated diffusion.
• Active Transport: This requires energy, often in the form of ATP, to move substances against their concentration gradient. Active transport is essential when cells need to accumulate substances in higher concentrations than found outside.

Understanding these mechanisms helps elucidate how cells acquire nutrients, expel waste, and stay in balance with their external environment.