unit 18 Cell Membranes and Movement Vocabulary

Flashcards covering key vocabulary from the unit on cell membranes and movement.

Cell

The smallest unit of life.

MRS GREN

Movement, reproduction, sensitivity, growth, respiration, excretion, and nutrition.

Diffusion

The net movement of particles from an area of high concentration to an area of low concentration.

Osmosis

The net movement of water molecules from a region of high water potential to an area of low water potential through a partially permeable membrane.

Active Transport

The movement of particles through a cell membrane from a region of lower concentration to a region of higher concentration using energy.

Photosynthesis

The process by which plants and some bacteria synthesize food molecules.

Respiration

The chemical processes that break down nutrient molecules in living cells to release energy.

Gas Exchange

A physical process in which oxygen is exchanged for carbon dioxide across a membrane surface.

Animals/Plants

Multicellular organisms consisting of many cells that work together.

Nucleus

Contains genetic material, including DNA

Cell membrane

Controls the movement of substances in and out of the cell.

Cytoplasm

A jelly-like material that contains dissolved nutrients and salts and structures called organelles, where many chemical reactions happen

Mitochondria

Organelles that contain the enzymes for aerobic respiration, and where most energy is released in respiration.

Ribosomes

Site of protein synthesis.

Chloroplast

Contains the green pigment, chlorophyll, which absorbs light energy for photosynthesis and the enzymes needed for photosynthesis.

Cell wall

Made from cellulose fibres and strengthens the cell and supports the plant.

Permanent vacuole

Filled with cell sap to help keep the cell turgid.

Tissue

A group of cells with a similar structure and function working together to do a particular job.

Organ

Made from a group of different tissues that all work together to do a particular job.

Organ System

Made from a group of different organs that all work together to do a particular job.

Breathing

Ventilation

Heart

The pump of the circulatory system.

Arteries

Carry blood from the heart to the other organs of the body.

Veins

Carry blood from the body's organs towards the heart.

Capillaries

Tiny vessels with very thin walls where the exchange of materials between cells and blood takes place.

Blood

A tissue, consisting of fluid called plasma in which blood cells are suspended, that transports substances around the body.

Red Blood Cells

Cells that contain hemoglobin to carry oxygen.

White Blood Cells

Cells that help to protect the body against infection.

Platelets

Cell fragments that help the blood to clot.

Plasma

The fluid part of the blood, which transports blood cells, nutrients, and waste products.

Alveoli

Tiny air sacs in the lungs where gas exchange occurs.

Trachea

The windpipe that carries air to the lungs.

Bronchi

The two main air passages that branch from the trachea, one to each lung.

Lungs

The main organs of the respiratory system where gas exchange takes place.

Diaphragm

A sheet of muscle separating the chest cavity from the abdomen; its contraction increases the volume of the chest cavity and so inflates the lungs.

Enzymes

Biological catalysts that speed up chemical reactions in living organisms.

Substrate

The substance on which an enzyme acts.

Active Site

The region of an enzyme where the substrate binds and where catalysis occurs.

Denaturation

A structural change in a protein that results in a loss of its biological properties.

Optimum Temperature

The temperature at which an enzyme is most active.

Optimum pH

The pH at which an enzyme is most active.

Amylase

An enzyme that catalyzes the hydrolysis of starch into sugars.

Catalase

An enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen.

Lipase

An enzyme that catalyzes the hydrolysis of fats (lipids).

Protease

An enzyme that breaks down proteins into peptides and amino acids.

Nucleus

The control center of the cell, containing DNA and responsible for coordinating cell activities.

Cell Membrane

A selectively permeable barrier that regulates the transport of substances into and out of the cell.

Cytoplasm

A jelly-like substance within the cell that contains organelles and is the site of many chemical reactions.

Mitochondria

Organelles responsible for generating energy (ATP) through cellular respiration.

Ribosomes

Sites of protein synthesis within the cell.