p1 bio

Comprehensive practice flashcards covering eukaryotic and prokaryotic cells, the human digestive system, communicable and noncommunicable diseases and their interactions, and the process and limiting factors of photosynthesis.

Eukaryotes

Organisms made of eukaryotic cells that contain their genetic material enclosed in a nucleus, including animals and plants.

Eukaryotic Cells

Cells that contain their genetic material enclosed in a nucleus.

Nucleus

The cellular structure in eukaryotic cells that contains the genetic material (DNA).

DNA (Eukaryotes)

The genetic material enclosed within the nucleus of an animal or plant cell.

Cell Membrane (Eukaryotes)

The structure found around the edge of animal and plant cells that encloses the cytoplasm.

Cytoplasm (Eukaryotes)

The cellular fluid located within the cell membrane of animal and plant cells.

Prokaryotes

Organisms, such as bacteria, composed of prokaryotic cells that lack a nucleus.

Prokaryotic Cells

Cells in which the genetic material is not enclosed in a nucleus.

Size of Prokaryotic Cells

Prokaryotic cells are much smaller in size than eukaryotic cells.

Bacterial Genetic Material

The primary genetic material of a bacterium consisting of a single loop of DNA not enclosed in a nucleus.

Plasmids

Small rings of DNA that may be present inside bacterial cells.

Bacterial Cell Wall

An outer structural layer present in bacterial cells, distinct from a plant cell wall.

Cell Membrane (Prokaryotes)

A membrane present in bacterial cells situated underneath the bacterial cell wall.

Cytoplasm (Prokaryotes)

The fluid substance inside a bacterial cell containing its genetic loop and plasmids.

Animal Cells

Eukaryotic cells containing a nucleus, cell membrane, and cytoplasm, but lacking a cell wall.

Plant Cells

Eukaryotic cells that possess a nucleus, cell membrane, cytoplasm, and a plant cell wall.

Cell Membrane vs. Cell Wall Distinction

The critical distinction that the boundary around animal cells is a cell membrane and must not be called a cell wall.

Plant Cell Wall vs. Bacterial Cell Wall

The cell wall found in plants is distinct from the bacterial cell wall found in prokaryotes.

Shared Features of Animal and Plant Cells

Both animal and plant cells possess a nucleus, a cell membrane, and cytoplasm.

Defining Characteristic of Eukaryotic DNA

The genetic material is enclosed within a nucleus.

Defining Characteristic of Prokaryotic DNA

The genetic material is not enclosed in a nucleus, consisting instead of a loop of DNA and plasmids.

Single Loop of DNA

The structural arrangement of the primary chromosomal DNA found in prokaryotic bacteria.

Function of Plasmids

Small additional rings of DNA found in bacteria that exist separately from the main loop of DNA.

Cellular Organisation of Bacteria

Single-celled prokaryotic organisms possessing a cell wall, cell membrane, cytoplasm, a loop of DNA, and optional plasmids.

Specialised Cells

Cells that have developed adaptations to help them carry out a specific function.

Muscle Cells

Specialised cells that contract (get shorter) to produce movement, containing protein fibres and abundant mitochondria.

Protein Fibres (Muscle Cells)

Special fibres contained in muscle cells that can change their length to allow the cell to contract.

Mitochondria (Muscle Cells)

Organelles packed into muscle cells that provide the energy needed for muscle contraction.

Muscle Cell Contraction

The process where muscle cells shorten, powered by energy from mitochondria and changing protein fibre lengths.

Tissue

A group of cells with a similar structure and function.

Muscle Tissue

A tissue formed by muscle cells working together to bring about contraction.

Organ

A group of tissues working together for a specific function.

Stomach

An organ that digests food using muscle tissue to churn food and glandular tissue to release enzymes.

Glandular Tissue (Stomach)

Tissue in the stomach that releases digestive enzymes.

Organ System

A group of organs working together to perform specific functions and form organisms.

Digestive System

An organ system where large food molecules are broken down into small molecules by enzymes and absorbed into the bloodstream.

Nutrients in Food

The three main large nutrients found in food: carbohydrates, proteins, and lipids.

Carbohydrates

A main food nutrient category that includes large molecules such as starch.

Starch

A large carbohydrate molecule that is digested into smaller sugar molecules.

Proteins (Digestive System)

Large nutrient molecules whose digestion begins in the stomach and continues in the small intestine.

Lipids

Large food nutrient molecules, also called fats, that require enzyme action and bile to be broken down.

Digestion

The process in which large food molecules are broken down into small molecules by enzymes so they can be absorbed into the bloodstream.

Absorption (Digestion)

The passage of small digested food molecules from the digestive system into the bloodstream.

Saliva Enzymes

Enzymes in the mouth that begin the digestion of starch into smaller sugar molecules.

Oesophagus

The muscular tube through which chewed food travels from the mouth to the stomach.

Hydrochloric Acid (Stomach)

Acid present in the stomach that helps digestive enzymes break down proteins.

Churning Action of the Stomach

Muscular action of the stomach that turns food into a fluid, increasing the surface area for enzymes to digest.

Pancreas

An organ that releases enzymes into the small intestine to continue digesting starch and protein and start digesting lipids.

Liver

An organ that releases bile into the small intestine to aid in lipid digestion and neutralise acid.

Bile

A chemical produced by the liver that speeds up the digestion of lipids and neutralises stomach acid in the small intestine.

Acid Neutralisation by Bile

The role of bile in neutralising the acidic fluid emerging from the stomach as it enters the small intestine.

Small Intestine (Digestive Enzymes)

The organ whose walls release enzymes that continue the digestion of proteins and lipids.

Small Intestine (Absorption Mechanisms)

The site where digested small food molecules enter the bloodstream either by diffusion or by active transport.

Active Transport (Small Intestine)

One of the two transport mechanisms used to absorb small food molecules into the bloodstream.

Large Intestine

The organ where water is absorbed from fluid into the bloodstream before feces is released from the body.

Communicable Diseases

Diseases that can be spread from person to person, caused by pathogens such as bacteria or viruses.

Pathogens

Microorganisms such as bacteria or viruses that spread communicable diseases.

Measles

An example of a communicable disease that can be spread from person to person.

Noncommunicable Diseases

Diseases that cannot be passed from person to person, such as coronary heart disease.

Coronary Heart Disease

An example of a noncommunicable disease that cannot be spread between individuals.

Health

The state of physical and mental well-being.

Causes of Ill Health

Factors causing poor health, including communicable diseases, noncommunicable diseases, poor diet, high stress, and harmful chemicals.

High Levels of Stress

A lifestyle factor that can cause ill health by negatively impacting physical and mental well-being.

Harmful Chemicals (Health)

Environmental factors in life situations that can lead to ill health and negatively affect physical and mental well-being.

Disease Interaction

A situation where having one disease increases the risk of, causes, or triggers another disease.

Tuberculosis (TB)

A communicable lung disease caused by bacteria that can be fatal.

Tuberculosis Pathogen

The bacterium responsible for causing tuberculosis.

Defective Immune System

A weakened immune defence system that leaves an individual much more likely to suffer from infectious diseases.

HIV

A disease that results in a defective immune system, increasing susceptibility to infectious diseases like TB.

Interaction Between HIV and TB

A disease interaction where HIV damages the immune system, making a person much more likely to contract and suffer from TB.

Human Papillomavirus (HPV)

An extremely common virus that is harmless in most people but can cause cervical cancer by infecting cervical cells.

Cervical Cancer

A cancer of the cervix that is most commonly caused by infection with HPV.

UK Cervical Cancer Incidence

Around $3000$ women are diagnosed with cervical cancer every year in the UK.

Interaction Between HPV and Cervical Cancer

A disease interaction where infection with one disease (HPV) causes another disease (cervical cancer).

Allergies

Conditions, such as asthma or dermatitis, that can be triggered by the immune system after fighting off an infection.

Asthma (Immune-Triggered)

An allergic condition that can be triggered by the immune system after defending against a pathogen.

Dermatitis

An allergic skin condition that can be triggered by the immune system following a pathogen infection.

Immune System-Triggered Disease

A disease interaction where the immune system clears a pathogen but leaves the individual with an allergy.

Arthritis

A very painful joint condition that can make it difficult for individuals to move and lead a normal life.

Interaction Between Arthritis and Depression

A disease interaction where the pain and isolation caused by a physical illness (arthritis) triggers a mental illness (depression).

Light Energy (Plants)

The source of energy trapped by plants to drive photosynthesis and fuel growth.

Photosynthesis

The chemical reaction plants use to trap light energy and convert carbon dioxide and water into glucose and oxygen.

Endothermic Reaction (Photosynthesis)

A reaction that takes in energy from its surroundings, which applies to photosynthesis taking in light energy.

Leaves

The plant organs where photosynthesis takes place, containing chlorophyll to absorb light.

Chlorophyll

The green chemical found in plant leaves that absorbs light energy for photosynthesis.

First Stage of Photosynthesis

The stage in which carbon dioxide and water enter the leaf and light energy is absorbed by chlorophyll.

Chemical Formula for Carbon Dioxide

The chemical formula $CO_2$.

Chemical Formula for Water

The chemical formula $H_2O$.

Chemical Formula for Glucose

The chemical formula $C_6H_{12}O_6$.

Chemical Formula for Oxygen

The chemical formula $O_2$.

Word Equation for Photosynthesis

$$\text{carbon dioxide} + \text{water} \rightarrow \text{glucose} + \text{oxygen}$$

Rate of Photosynthesis

The speed at which a plant performs photosynthesis to produce glucose and oxygen.

Limiting Factor

An environmental factor in short supply that restricts the rate of photosynthesis from increasing.

Light Intensity as a Limiting Factor

A condition where increasing the light intensity increases the rate of photosynthesis because light was in short supply.

Photosynthesis Rate at Zero Light Intensity

When light intensity is $0$, the rate of photosynthesis is $0$ because light is required for the reaction.

Light Intensity Plateau

The point where increasing light intensity no longer raises the photosynthetic rate because another factor is limiting.

Carbon Dioxide as a Limiting Factor

A condition where increasing the concentration of $CO_2$ in the air causes the rate of photosynthesis to increase.

Carbon Dioxide Plateau

The point where increasing $CO_2$ level no longer raises the photosynthetic rate because $CO_2$ is no longer the limiting factor.

Patches of Chlorophyll

Patches on leaves containing less chlorophyll that trap less light energy, resulting in a lower rate of photosynthesis.

Temperature Effect and Enzyme Denaturation

As temperature rises, photosynthetic enzymes work faster, increasing rate; at excessive temperatures, enzymes denature and the rate falls.