B1-Cell Structure Flashcards
Nucleus
Controls the cell has dna and contains the genes on the chromosomes to carry instructions for making the proteins needed to new cells or organisms.
Cytoplasm
Liquid gel where most chemical reactions needed for life take place and organelles are suspended.
Cell membrane
Controls the movement of substances in and out of the cell.
Mitochondria
Aerobic Respiration takes place releasing energy for the cell.
Ribosomes
Protein synthesis takes place here making all the proteins needed for the cell.
Cell wall
Made of cellulose strengthens and supports the cell.
Chlorophyll
Absorbs light for the cell to make photosynthesis for food.
Permanent vacuole
Made of water and cell sap makes cells rigid to support the plant.
Nerve cell
To carry nerve impulses to different parts of the body. Long, Connections at each end and Can carry electrical signals
Sperm cell
Job: To reach female cell, and join with it. Special features: Long tail for swimming and Head for getting into female cell
Muscle cell
Job: move bones. Special features: Lots of mitochondria to produce energy, Long and skinny to help cells contract and extend for movement and Lots of nuclei to help large cell communicate
Red blood cell
Job: to carry oxygen around the body. Special features: Large surface area, for oxygen to pass through, Contains haemoglobin, which joins with oxygen and Contains no nucleus
Root hair cell
Absorb water and minerals and has a large surface area including a fold
Ciliated epithelial cell
Job: move particles out of your body. Special features: Microvilli bumpy extension of apical surface increases surface area and absorption rate. Goblet cells single cell glands which produce protective mucus
Eukaryotes
Cells of animals, plants and fungi are called eukaryotic cells. They contain membrane bound organelles such as a nucleus and mitochondria.
Prokaryotes
These cells do not contain membrane bound organelles such as a nucleus and mitochondria.
Bacterial cells are called prokaryotic cells.
How are eukaryotic and prokaryotic cells similar
Prokaryotes and eukaryotes have some structures in common:
Cell membrane
Cytoplasm
Cell wall (in some eukaryotes)
How are eukaryotic and prokaryotic cells different?
Prokaryotes are simpler than the cells of eukaryotes and are smaller, most are 0.2 μm - 2.0 μm. Prokaryotic cells do not contain membrane bound organelles such as a nucleus and mitochondria. But have a single loop of DNA free in the cytoplasm and an additional circular piece of DNA called a plasmid, used to transfer genetic material from one cell to another. As well as prokaryotes do not have vacuoles and chloroplasts that some eukaryotes have.
Magnification
Is the act or process of enlarging the physical appearance or image of something.
Resolution
The number of pixels in a digital image is known as the image resolution. The resolution is measured in dots per inch (sometimes called pixels per inch)
Equation: magnification=
Size of image/ size of real object
Exchange surfaces
Every organism, whatever its size needs to exchange materials with the environment.
How easy the exchange of substances is depends on the organism’s surface area to volume ratio (SA: V ratio).
The smaller the organism, the larger its surface area to volume ratio.
Photosynthetic
cells
Function: So plants can produce their own food by photosynthesis adaptions: Chloroplasts containing chlorophyll that trap the light needed, large permanent vacuole helps keep cell rigid as result of osmosis
Xylem cells
Function: Carry water and mineral ions from the roots to the highest leaves and shoots and also helps support the plant
Adaptions: Cells die and from long hollow tubes that allow the water and minerals to move easily, spirals and rings of lignin make them strong so they can withstand pressure
