Cell Structure Flashcards

Question

What does haemotoxylin stain and it’s colour

Answer 1

RNA purple | DNA blue

Answer 2

Organelles are often transparent so it prevents object from appearing white

Answer 3

Actual = image/ magnification

Answer 4

Uses laser beams to scan a specimen, tagged with fluorescent dye Laser beam is focused through a lens which is aimed at a beam splitter Beam splits and some light is directed to specimen When the laser hits dye it gives off fluorescent light Light if focused through pinhole onto a detector Detector is hooked to a computer which generates the image

Answer 5

Treat it with heavy metals (like lead) | Metal ions scatter electrons foraged at the sample and give contrast between different structures

Answer 6

Use a thinly sliced specimen Use tweezers to place specimen in the middle of a clean slide Place a cover slip on top

Answer 7

Observing hairs, Parts of insects Pollen Parts of a flower

Answer 8

Pipette a small drop of water onto the slide Use tweezers to place specimen on water droplet Stand cover slip upright near water droplet Carefully tilt and lower slip so it covers the specimen Try to avoid air bubbles Add a stain to edge of cover slip, drawing the stain across the specimen

Answer 9

Living samples eg tiny aquatic organisms

Answer 10

1. Clip the slide containing the specimen onto the stage 2. Select lowest powered objective lens 3. Use coarse adjustment knob to bring stage up to just below objective lens 4. Look down eyepiece, using coarse adjustment knob to move stage until image is in focus 5. Adjust focus with fine adjustment knob until you get a clear image 6. Swap to higher powered objective lens if required

Answer 11

It is fitted onto the eyepiece Like a transparent ruler with numbers but no units When you look through eyepiece you’ll see a scale

Answer 12

Placed on the stage It is a microscope slide with an accurate scale (has units) Used to work out value of divisions on the eyepiece graticule at a particular magnification

Answer 13

Different stains can be used to make different parts of cell show up

Answer 14

Large organelles surrounded by nuclear envelope (double membrane) Contains many pores Contains chromatin (made of DNA and proteins) Contains a nucleolus Controls cells activities by controlling transcription of DNA DNA contains instructions to make proteins Pores allow substances to move between nucleus and cytoplasm Nucleolus makes ribosomes

Answer 15

Made of lipids and proteins Regulates movement of substances in/out of cell Has receptor molecules which allow it to respond to chemicals like hormones

Answer 16

Rigid structure that surrounds plant cells Made of cellulose Supports plant cells

Answer 17

Round organelle surrounded by a membrane with no clear internal structure Contains digestive enzyme To digest invading cells or break down worn out components Transports hydrologic enzymes

Answer 18

System of membranes enclosing a fluid filled space Surface is covered with ribosomes Folds and processes proteins made at the ribosomes

Answer 19

System of membranes enclosing a fluid filled space Synthesises and processes lipids and steroid hormones

Answer 20

Small fluid filled sac in the cytoplasm surrounded by a membrane Transports substances in/out of cell via plasma membrane Some are formed by Golgi apparatus or ER and some at the cell surface

Answer 21

Group of fluid filled membrane bound flattened sacs Vesicles at the edges of the sacs Processes and packages new lipids and proteins Makes lysosomes

Answer 22

Double membrane Inner membrane folded to form cristae Inside is the matrix which contains enzymes for respiration Site of aerobic respiration where ATP is produced Found in large numbers in cells that are active and require a lot of energy

Answer 23

Small flattened structure found in plants Surrounded by double membrane Membranes inside called thylakoid membranes Thylakoid are stacked up to form grana Grana are linked together by lamellae - thin flat pieces of thylakoid membrane Site of photosynthesis Some photosynthesis happen in grana and other parts in the stroma (thick fluid in chloroplasts)

Answer 24

Small hollow cylinders made of microtubules (tiny protein cylinders) Found in animal cells but only some plant cells Involved in separation of chromosomes during cell division

Answer 25

Small hair like structures found on the surface membrane of some animal cells Cross section - outer membrane and a ring of 9 pairs of protein microtubules inside and a single pair in the middle Microtubules allow cilia to move Movement is used by the cell to move substances along the cell surface

Answer 26

Flagella on eukaryotic cells are like cilia but longer Stick out from the cell surface Surrounded by plasma membrane Two microtubules in centre and 9 pairs around the edge Microtubules contract to make flagellum move Flagella propel cells forward (eg when sperm swims to egg)