Term
|
Definition
| All living things are made up of one or more cells, and all cells come from pre-existing cells. |
|
|
Term
| Definition of living things |
|
Definition
- complex and have an organised structure
- take in and use energy from their surroundings
- have a chemically different composition to their environment
- respond to stimuli
- can reproduce
- grow and develop
|
|
|
Term
| Cells are the smallest individual units of life because... |
|
Definition
| They are the smallest entity that can fulfill all of the requirements of living things (respond to stimuli, grow and develop, reproduce, chemically different composition to their environment, take in and use energy from surroundings, are complex and have an organised structure.) |
|
|
Term
| Surface area to volume ratio |
|
Definition
| As size increases, surface area to volume ratio decreases. As the cell gets bigger there is less surface area therefore it is less efficient at exchanging materials with its surroundings (taking in nutrients and excreting wastes) |
|
|
Term
Prokaryotes vs Eukaryotes Prokaryotes |
|
Definition
Smaller (1-10um diameter) simple No internal organisation No nucleus (DNA single stranded; often plasmid) Have ribosomes May have cell wall Are monera (bacteria) |
|
|
Term
Prokaryotes vs Eukaryotes
Eukaryotes |
|
Definition
larger, 10-100 um complex highly organised have membrane bound organelles double stranded DNA have ribosomes are protists, fungi, plants or animal cells |
|
|
Term
|
Definition
| Discrete structural bodies within the cell such as the nucleus, mitochondrian and ribosomes. |
|
|
Term
|
Definition
- Double membrane boundary (nuclear envelope which contains pores lined with proteins)
- Contains chromatin (made up of DNA and protein)
- The DNA stores the cells hereditary material and provides info needed for cell to function
- Contains one or more nucleoli (sing. nucleolus) - black circle, site of RNA synthesis
|
|
|
Term
|
Definition
Mitochondria, looks like shoe sole Has outer and inner membrane folded into cristae. releases energy from the latter stages of aerobic respiration which are carried out insidethe mitochondria |
|
|
Term
|
Definition
Have 2 outer membranes, looks like its filled with tiger worms (thykaloids, the black bits are grana which are stacks of thykaloids) surrounded by fluid called stroma. Thykaloids help photosynthesis, contain chlorophyll and other photosynthetic pigments |
|
|
Term
|
Definition
Fluid filled space bound by a membrane. Contains a watery solution of salts (in the form of ions), simpls sugars, and amino acids Responsible for maintaining salt and water balance of cell, & contrubutes to cell growth by taking in water and enlarging. May also be used to store cell wastes |
|
|
Term
|
Definition
system of membranes that extends throughout the cytoplasm from the nuclear envelop to the cell membrane.important for internal cell transport Rough ER - has ribosomes, is the site of protein and membrane synthesis. Smooth ER - involved in metabloic processes such as lipid synthesis and carbohydrate metabolism |
|
|
Term
|
Definition
Looks kind of like a ultrasound sometimes, or dog poo when its in 3D. Stacks of flattened sacs made of smooth membrane. Involved in the packaging and secretion of proteins. Lots are found in glands. Also makes carbohydrates which it secrets by exocytosis |
|
|
Term
| Why even the smallest cell has several hundred genes |
|
Definition
| Because even the smallest cell has many compounds that it needs to make, and genes contain the information needed to produce these compounds |
|
|
Term
Function of the cell membrane |
|
Definition
To regulate the passage of materials and keep it distinguishable from its surroundings Enable attachment of the cytoskeleton Enable cells to recognize each other |
|
|
Term
|
Definition
In eukaryotic cells Made of 3 main components: microfilaments, intermediate filaments, microtubules These components are made up of globulare proteins |
|
|
Term
|
Definition
Give cells shape To be involved in cell movement (forming of spindle, cell division) To hold organelles in place To strengthen cells |
|
|
Term
Cell membrane Fluid Mosaic Model Structure |
|
Definition
| Double layer of phospholipids, penetrated by protein molecules at various points. Carbohydrates branch off of proteins as receptors, enabling cells to recognise each other |
|
|
Term
|
Definition
The random movement of particles from a region of higher concentration to a region of lower concentration until equilibrium. |
|
|
Term
|
Definition
Diffusion across a semi-permeable membrane to e region of higher concentration |
|
|
Term
|
Definition
Certain substances can pass through the membrane because proteins act as channels or gates to let them through. Carrier proteins also help get some substances through |
|
|
Term
|
Definition
| Proteins in the membrane bind to certain ions or molecules (eg glucose) and carry them across the membrane |
|
|
Term
|
Definition
Movement of substances across the membrane against the concentration gradient. Uses energy(ATP), requires a living cell, uses membrane carrier proteins. |
|
|
Term
|
Definition
| Cells taking in particles or large molecules by enclosing them in a membranous vacuole. Phagocytosis is large scale pinocytosis is small scale. |
|
|
Term
|
Definition
| Membrane invaginates in the vacinity of the particle, and encloses it in a vacuole which breaks away from the membrane. Lysosomes fuse with the vacuole, and release digestive enzymes to break down the particle. |
|
|
Term
|
Definition
Light energy is used to synthesise complex organic compounds from simple inorganic substances. Used by organisms called autotrophs 6CO² + 6H²O → C(6)H¹²O(6) + 6O² (chlorophyll + L.E)
|
|
|
Term
|
Definition
| Making chemical bonds releases energy, breaking them uses up energy. Some bonds are made and broken in chemical reactions, a net output of energy is achieved when more energy is released than used |
|
|
Term
|
Definition
Adenosine triphosphate, consists of adenine bonded to ribose sugar, which is bonded to three phosphate groups (triphosphate). ATP is hydrolised (water added), third phosphate breaks away too make ADP + P and energy is released. This reaction uses energy from cell respiration |
|
|
Term
|
Definition
Interphase, Prophase, Metaphase, Anaphase, Telophase Occurs in eukaryotic cells |
|
|
Term
|
Definition
Centrioles double and migrate to poles condensing of chromatin into chromosome form nuclear membrane breaks down spindle forms. Looks like a jumble of chromosomes with an asterix shape at the north and south points of the cell |
|
|
Term
|
Definition
| Chromosomes line up in centre horizontally. spindle fibre is visible |
|
|
Term
|
Definition
| Sister chromatids separate, looks like a mouth with banana shaped teeth. Spindle fibre and poles (asterixes) are still visible |
|
|
Term
|
Definition
| chromosome unwinds, spindle breaks down nuclear membrane reforms. Looks like boobs. |
|
|
Term
|
Definition
| Cell membrane pinches in and two new cells are formed |
|
|
Term
|
Definition
| occurs in prokaryotic cells. Cells contain a circular chromosome (looks like a teardrop), DNA is replicated, cell grows, as membrane stretches the two chromosomes pull apart until seperated, the cell splits in two and tada.. two new cells |
|
|
