Human bio cells, tissues, metabolism

Define cell

The smallest unit of life capable of carrying out all vital functions.

Define organelle

A specialized structure within a cell that performs a specific function.

Cell membrane function

Controls what enters and leaves the cell.

Mitochondria function

Produces ATP through cellular respiration.

Ribosome function

Site of protein synthesis.

Golgi body function

Modifies, sorts, and packages proteins.

Nucleus function

Stores DNA and controls cell activities.

Nucleolus function

Produces ribosomes.

Lysosome function

Breaks down waste and cellular debris.

Cytoplasm

Jelly-like fluid where many metabolic reactions occur.

Endoplasmic reticulum

Network that synthesizes and transports proteins and lipids.

Vesicle

Small membrane sac used for transport within the cell.

Centriole

Helps organize spindle fibers during cell division.

Structure of cell membrane

Phospholipid bilayer with proteins (fluid mosaic model).

Selective permeability

The membrane allows some substances to pass but not others.

Passive transport

Movement of substances down a concentration gradient without energy.

Active transport

Movement of substances against the gradient using ATP.

Simple diffusion

Movement of molecules from high concentration to low concentration.

Facilitated diffusion

Diffusion using membrane transport proteins.

Osmosis

Diffusion of water across a selectively permeable membrane.

Endocytosis

Cell takes materials into the cell using vesicles.

Pinocytosis

“Cell drinking” – uptake of liquids.

Phagocytosis

“Cell eating” – engulfing large particles.

Exocytosis

Vesicles fuse with the membrane to release substances outside the cell.

Surface area to volume ratio

Limits how large cells can grow because exchange becomes inefficient.

Levels of organization

Cell → Tissue → Organ → Organ system → Organism.

Tissue definition

Group of similar cells working together to perform a function.

Four tissue types

Epithelial, connective, muscle, nervous.

Organ definition

Structure made of different tissues working together.

Organ system

Group of organs working together to perform a major function.

Organism

An individual living thing.

Metabolism

All chemical reactions occurring in a cell.

Anabolism

Building complex molecules from smaller ones.

Catabolism

Breaking down molecules to release energy.

Carbohydrates function

Main source of cellular energy.

Lipids function

Long-term energy storage and membrane structure.

Proteins function

Enzymes and structural components.

Nucleic acids function

Store and transmit genetic information.

Oxygen role

Used in aerobic respiration.

Water role

Solvent and medium for metabolic reactions.

Vitamins

Help enzymes function properly.

Minerals

Support structure and metabolic processes.

Enzyme

Biological catalyst that speeds up chemical reactions.

Active site

Region where the substrate binds to the enzyme.

Substrate

Molecule the enzyme acts on.

Enzyme-substrate complex

Temporary complex formed when enzyme binds substrate.

Lock and key model

Substrate fits exactly into enzyme active site.

Factors affecting enzymes

Temperature, pH, substrate concentration, enzyme concentration.

Cellular respiration

Process that releases energy from glucose to make ATP.

Aerobic respiration

The complete breakdown of glucose to carbon dioxide and water, requires oxygen.

First step of aerobic respiration

Pyruvate converts into acetyl CoA. No atp is produced.

Citric acid cycle (Krebs cycle)

Carbon atoms in the acetyl CoA are released in carbon dioxide. Every CoA that enters, one molecule of atp is produced. Meaning each glucose molecule produces 2 atp molecules.

Electron transport system.

Electrons are passed between molecules, resulting in oxygen molecules forming water. Roughly 26-34 atp molecules are produced here.

Anaerobic respiration

Respiration without oxygen producing small amounts of ATP.

Aerobic respiration equation

Glucose + Oxygen → Carbon dioxide + Water + ATP.

Anaerobic respiration equation

Glucose → Lactic acid + ATP (animals) or Ethanol + CO₂ + ATP (yeast).

Location of aerobic respiration

Mainly in the mitochondria.

Location of anaerobic respiration

In the cytosole.

ATP-ADP cycle

ATP releases energy when converted to ADP and phosphate.

Uses of ATP

Active transport, biosynthesis, movement, cell division.

Nutrients for metabolism

Carbohydrates, proteins, lipids, vitamins, minerals, and water.

Glycolysis

First phase in breakdown of glucose, does not require oxygen. Broken down into 2 molecules called pyruvic acid.

Production of lactic acid

Formation of lactic acid from glucose without oxygen (anaerobic respiration)

How many atp molecules are formed in anaerobic respiration

One molecule of glucose converts 2 adp molecules to atp

Uses and products of anaerobic respiration

Used glucose to produce lactic acid and 2 atp molecules

ATP produced from aerobic respiration

Potential of up to 38. 2 from glycolysis, 2 from citric acid cycle, up to 34 from electron transport mechanism.

Cellular respiration equation

C^6​H^12​O^6​+6O2​→6CO2​+6H^2​O+energy (ATP)

Glucose + oxygen → carbon dioxide + water + energy (ATP)

Epithelial tissue

Covering or lining tissue

Connective tissue

Provides support for the body and helps to hold all the body parts together

Muscle tissue

Long and thin and can contract to become shorter.

Nerve tissue

Made of specialised nerve cells called neurons. Carries messages