Cell Biology, Chemistry, and Physics Lecture Review

Comprehensive practice flashcards covering Integrated Science topics from biology, chemistry, and physics, based on GCSE level knowledge organisers.

What are the two major types of eukaryotic cells?

Animal and plant cells

How is the genetic material organized in a prokaryotic cell?

It consists of a single loop of DNA and may contain small rings of DNA called plasmids, but does not have a nucleus.

Which sub-cellular structure is the site of protein synthesis?

Ribosomes

How do mitochondria support the function of a sperm cell?

They release energy from respiration, which enables the sperm cell to swim to the ovum.

What is the formula for calculating the magnification of an image?

$$\text{magnification} = \frac{\text{image size}}{\text{actual size}}$$

Define active transport.

The movement of particles against a concentration gradient, from a more dilute solution to a more concentrated solution, using energy from respiration.

What takes place during the second stage of the cell cycle (mitosis)?

A complete set of chromosomes is pulled to each end of the cell and the nucleus divides to form two nuclei.

What is therapeutic cloning?

A process where cells from a patient's own body are used to create a cloned early embryo, providing stem cells with the same genes that are less likely to be rejected.

How does the 'lock and key' theory describe enzyme action?

The substrate (key) fits into the enzyme's active site (lock) because the active site is a specific shape.

Which enzyme breaks down starch into glucose?

Amylase

Why is the human circulatory system described as a double circulatory system?

Because blood passes through the heart twice for every circuit around the body: the right ventricle pumps blood to the lungs and the left ventricle pumps blood to the body.

What is the function of the xylem in plants?

To transport water and mineral ions from the roots to the rest of the plant.

Define translocation.

The movement of dissolved sugars from the leaves to the rest of the plant through the phloem.

Which type of pathogen causes Malaria?

Protists

How do vaccinations provide immunity?

They involve injecting small quantities of dead or inactive pathogens into the body, stimulating lymphocytes to produce antibodies so they can be produced quickly if the pathogen re-enters.

What is the primary difference between malignant and benign tumors?

Malignant tumors are cancerous and spread to other parts of the body via the blood to form secondary tumors, while benign tumors are non-cancerous and do not spread.

State the balanced symbol equation for photosynthesis.

$$6CO_2 + 6H_2O \rightarrow C_{6}H_{12}O_6 + 6O_2$$

What is the inverse square law for light intensity as the distance from a plant increases?

$$\text{light intensity} \propto \frac{1}{\text{distance}^2}$$

State the word equation for anaerobic respiration in yeast cells (fermentation).

$$\text{glucose} \rightarrow \text{ethanol} + \text{carbon dioxide}$$

Define oxygen debt.

The amount of oxygen needed to react with the accumulated lactic acid to remove it from cells after exercise.

Which part of the brain coordinates muscle activity?

Cerebellum

How is Type 2 diabetes typically treated?

Commonly treated with a carbohydrate-controlled diet and exercise because the body cells no longer respond to the insulin produced.

What is the function of Luteinising Hormone (LH) in the menstrual cycle?

It stimulates the release of a mature egg from the ovaries (ovulation).

What is a genome?

The entire genetic material of an organism.

What is the relative charge and mass of a neutron?

Relative charge is $0$ and relative mass is $1$.

Define isotopes.

Atoms of the same element that have the same number of protons but different numbers of neutrons.

Why did Mendeleev leave gaps in his early version of the Periodic Table?

To account for undiscovered elements, whose properties he predicted based on the gaps.

Why does reactivity increase as you go down Group 1 (the alkali metals)?

The atoms increase in size, so the outer electron is further from the nucleus and more shielded, making the electrostatic attraction weaker and the electron easier to lose.

How is an ionic bond formed?

By the transfer of electrons from a metal atom to a non-metal atom, resulting in oppositely charged ions that are held together by strong electrostatic attraction.

Why is graphite soft and slippery?

The carbon atoms form hexagonal rings in layers that are not covalently bonded together, allowing the layers to slide over each other.

State the formula for calculating moles from mass.

$$\text{moles} = \frac{\text{mass}}{M_r}$$

What does the Law of Conservation of Mass state regarding a chemical reaction?

The sum of the $M_r$ of the reactants equals the sum of the $M_r$ of the products.

In terms of electrons, define oxidation and reduction (REDOX).

Oxidation is the loss of electrons and reduction is the gain of electrons.

What is an electrolyte?

A liquid or solution that contains ions and can therefore conduct electricity.

Define activation energy.

The minimum amount of energy that particles must have to react when they collide.

What is Le Châtelier’s principle?

If a change is made to the conditions of a system at equilibrium, the system will counteract that change.

What is the general formula for alkanes?

$$C_n H_{2n+2}$$

How are the hydrocarbons in crude oil separated?

Through fractional distillation, which separates them based on their different boiling points.

State the formula for kinetic energy.

$$E_k = \frac{1}{2}mv^2$$

Define power in physics.

The amount of energy transferred or work done per second, measured in Watts ($W$).

What is the equation for efficiency as a decimal?

$$\text{efficiency} = \frac{\text{useful energy output (J)}}{\text{total input energy (J)}}$$

Define specific heat capacity.

The amount of energy needed to raise the temperature of $1\,kg$ of a substance by $1\,^{\circ}C$.

State Ohm's Law (the relationship between current, potential difference, and resistance).

$$V = IR$$

What are the colors and potential differences of the three wires in a UK mains cable?

Live wire is brown ($230\,V$), neutral wire is blue ($0\,V$), and earth wire is green/yellow ($0\,V$).

Define the specific latent heat of fusion.

The energy required to melt $1\,kg$ of a substance at its melting point with no change in temperature.

What is a half-life of a radioactive source?

The time taken for the number of unstable nuclei in a sample to halve, or for the activity/count rate to halve.

State Newton's Second Law.

$$\text{resultant force (F)} = \text{mass (m)} \times \text{acceleration (a)}$$

List the waves of the electromagnetic spectrum in order of increasing frequency.

Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.