key terms and meanings Flashcards
mixed topics
what is a concentration gradient?
difference in number of molocules of a substance inside and outside of a cell
what is passive transport?
the movement of a substance through a membrane that does not require energy
what is diffusion?
the movement of molocules down the concentration gradient
what is osmosis?
water molocules moving from a high water concentration to a low water concentration through a selectivley permeable membrane.
what is the meaning of the word ‘turgid’?
when a plant cell becomes swollen as it takes in water by osmosis.
what happens during active transport?
the movement of molocules across the cell membrane against the concentration gradient. process require energy, proteins and ions
what is a chromosome?
a thread-like structure found in the nuclei of cells made up of DNA
what is DNA?
molocule that carries genetic information in the form of genes.
Has a double-stranded helix shape
what are the four bases?
Adenine
Thymine
Cytosine
Guanine
what is a gene?
a section of DNA which codes for a protein
what are the 5 different protein types?
- structural
- Hormones
- Antibodies
- Receptors
- Enzymes
what is a structural protein?
Structural component of a membrane
what is a hormone?
A chemical messenger
what is an antibody?
they defend the body against microorganisms
what is a receptor?
they allow other molecules to bind to them
