Grade 10 - Biology Definitions

Interphase

when the cell is functioning as normal before mitosis happens

Mitosis

is the process of dividing DNA

Chromatin

when chromosomes are all jumbled together in the nucleus during interphase

Chromosomes

DNA that is stored in long strands

Chromatid

a copy on the chromosome

Centromere

holds the 2 chromatids together as a chromosome

Centriole

an organelle in the cell that grows spindle fiber during mitosis

Spindle fiber

strands that grow from centrioles during mitosis, pulls chromosomes apart during anaphase

DNA checkpoint

checkpoints to check for DNA mutations and other issues during the process

Regeneration

this is when damage to the body can trigger rapid cell division to replace the lost or damaged part

Necrosis

traumatic cell death caused by damage or injury, triggers an immune response

Apoptosis

purposeful cell death that removes cells that no longer function or are not needed

Gene

a section of DNA which codes for a particular protein

Mutation

a change in the DNA code in a particular gene

Tumor

a solid cancer

Metastasis

the spread of cancerous cells through the blood stream to new locations in the body

Carcinogen

substances which are known to cause cancerous mutations

Screening

trying to find cancer before symptoms have started

Testing

trying to find cancer to explain symptoms

Chemotherapy

type of cancer treatment in which chemicals are used on the body that are toxic to cells undergoing mitosis

Prokaryotic

unicellular organisms that don't have nuclei, their genetic material is freely floating

Eukaryotic

multicellular organisms that store DNA in their nuclei

Unicellular

organisms made up of one cell

Multicellular

organisms made up of multiple cells

Cell Membrane

semipermeable membrane that separates the inside of the cell from its surroundings, allows some substances to flow in and out

Cytoplasm

a jellylike fluid that fills up the interior of the cell, surrounds the organelles and allows nutrients and organelles to float through it

Cytoskeleton

structure that holds the cell shape together, made from protein filaments

Nucleus

contains DNA, which contain instructions that can be used to create proteins

Nucleolus

where ribosomes are made

Rough Endoplasmic reticulum

surrounds the nucleus and is covered in ribosomes that help mRNA create protein

Smooth Endoplasmic Reticulum

create lipids and do not have ribosomes attached to them

Golgi Body (Apparatus)

modifies, sorts, and packages proteins for delivery around the cell

Mitochondria

powerhouse of the cell, responsible for cellular respiration which provides energy for the cells processes and contains its own DNA

Vacuole

contains and stores nutrients and waste

Lysosome

contain digestive enzymes which break down waste, old organelles and pathogens

Central Vacuole

stores water for plants and provides structure for the whole plant cell

Cell Wall

provide structure for plant cells and prevents cell from bursting when water is absorbed

Chloroplast

contain a molecule called chlorophyll, which facilitates photosynthesis

Simple diffusion

the movement of molecules along their concentration gradient without the use of energy.

Facilitated Diffusion

moving substances across the cell membrane by allowing them to diffuse through a protein channel

Active Transport

moving substances across the cell membrane, using a protein pump powered by energy to move the substance against its concentration gradient

Processes of life

Metabolism, growth and repair, movement, reaction to stimuli, reproduction

Specialized cells

certain cells that have some of their genes switched off

Stem cells

cells which have not differentiated yet, and can become anything

Embryonic stem cells

can become any type of animal cell

Adult stem cells

can only become a limited number of all types of cells

Tissue

groups of cells which work together to perform a function

Epithelial tissue

tightly packed cells which form a layer that is one or several cells thick

Connective tissue

joins other tissues together, supports structures, fills space

Nervous tissue

creates and transmits nerve impulses (electric signals) through the body

Semipermeable

allows some substances in or out as needed