U1T7 - Keywords

Question 1

Alimentary Canal

Answer 1

Part of the digestive system which forms a long hollow tube that runs from mouth to anus. Regionalised with highly adapted organs in specific regions.

Question 2

Chyme

Answer 2

Mix of food and gastric juice.

Question 3

Duodenum

Answer 3

First loop of the small intestine

Question 4

Pyloric Sphincter

Answer 4

Ring of muscle situated immediately between the end of the stomach and the duodenum.

Question 5

Muscularis Mucosa

Answer 5

Thin layer of muscle between mcosa and submucosa which helps movement of villi in mucosa. Keeps villi in contact with digestion products in gut lumen.

Question 6

Serosa

Answer 6

Very thin outermost protective + supportive lining of connective tissue in alimentary canal. Supports AC as it’s connected to mesentery which is connected to peritoneum of abdominal cavity.

Question 7

Mesentery

Answer 7

Fold of the peritoneum which attaches

stomach, small intestine, pancreas, spleen, and other organs to posterior wall of abdomen.

Question 8

Peritoneum

Answer 8

Serous membrane lining cavity of abdomen + covering abdominal organs.

Question 9

Serous

Answer 9

Serum-producing.

Question 10

Goblet Cells

Answer 10

Mucus secreting cells within columnar epithelial cells.

Question 11

Bile

Answer 11

Mixture of substances which aren’t all involved in digestion. Rich in bicarbonate which neutralises acid from stomach.

Question 12

Bile Salts

Answer 12

Digestive compounds. Emulsify fats by reducing surface tension of fat, breaking into tiny fat droplets, facilitating lipase.

Question 13

Crypts of Lieberkuhn

Answer 13

Deep folds in duodenum wall. Embedded in tissue between villi.

Question 14

Brunner’s Glands

Answer 14

Secrete intestinal juice containing water, mucus + sodium hydrogen carbonate. Doesn’t contain enzymes but protects mucosa of duodenum from stomach acid.

Question 15

Epidermis

Answer 15

Covers + protects leaf. First defence against physical damage.

Question 16

Upper Epidermis

Answer 16

Consists of 1+ layer rectangular cells. Terrestrial plants have waxy cuticle for waterproofing to reduce surface water loss by transpiration. Thicker on upper surface (shiny). No chloroplasts, transparent so allows light.

Question 17

Lower Epidermis

Answer 17

Has pores called stomata which allow CO2 + O2 to enter + H2O + O2 to exit. Stoma surrounded by guard cells to regulate open + close (close at night). GC’s have chloroplasts.

Question 18

Vascular Tissue

Answer 18

Consists of veins adapted for transport around plant. Made of vascular bundles.

Question 19

Vascular Bundles

Answer 19

Groups of vessels running from root up stem to leaves. Made up of xylem and phloem vessels.

Question 20

Xylem

Answer 20

Forms upper part of vascular bundle in leaf. Brings water for photosynthesis and minerals (inorganic ions) to leaf.

Question 21

Phloem Sleeve/Sieve-Tubes

Answer 21

Form lower part of vascular bundle in leaf. Transports sucrose (sugars) and other photosynthesis products from leaf to other parts of plant (translocation). Sucrose to plant storage regions (bulbs/tubers) + converted to starch or to actively growing regions for respiration.

Question 22

Palisade Mesophyll

Answer 22

Main photosynthesising region of leaf. Beneath upper epidermis to max light harvesting. Palisade cells are regularly arranged + packed with chloroplasts to max photosynthesis.

Question 23

Spongy Mesophyll

Answer 23

Beneath palisade mesophyll. Loosely packed, irregularly arranged cells. Air spaces for gaseous exchange. CO2 can diffuse up to palisade cells where photosynthesis occurs. Few chloroplasts. Large gas exchange surface.

Question 24

Tissues

Answer 24

Groups of similar cells that work together to carry out the same function. e.g. mesophyll tissue, muscle tissue.

Question 25

Organs

Answer 25

Several different types of tissue grouped together to form a structural unit which carries out one or more functions. e.g. leaf, ileum, stomach.

Question 26

Organ Systems

Answer 26

A group of organs which work together to perform a function. e.g. digestive system (ileum, mouth, oesophagus, stomach, pancreas, liver _ colon)

Question 27

Pinocytosis

Answer 27

Absorption of some substances. e.g. In babies, antibodies (proteins) pass from breast milk to blood system without being digested.

Question 28

Venules

Answer 28

Small Vein

Question 29

Villi

Answer 29

1mm projections of mucosa wall, each containing thousands of cells.

Question 30

Microvilli

Answer 30

0.6um projections of cell-surface membrane of epithelial cells lining mucosa.

Question 31

Specialised Cells

Answer 31

Adapted to carry out a particular function.

Question 32

Cell

Answer 32

Smallest unit that can carry out all 7 life processes. e.g.muscle cell, goblet cell, guard cell.

Question 33

Peristalsis

Answer 33

Involuntary contraction and relaxation of muscles of the intestine to push food forward.

Question 34

Segmentation

Answer 34

Division of a cell, cleavage.

Question 35

Pendular Movement

Answer 35

Swinging movement of intestine without peristaltic action, mixing food.

Question 36

Smooth Muscle

Answer 36

Muscle tissue in which contractile fibrils aren’t highly ordered, not under voluntary control.

Question 37

Arteriole

Answer 37

Small branch of artery leading into capillaries.

Question 38

Petiole

Answer 38

The stalk that joins a leaf to a stem.

Question 39

Midrib

Answer 39

Large strengthened vein along midline of leaf.

Question 40

Waxy cuticle

Answer 40

Protective layer covering leaf, reduces water loss by transpiration/evaporation.

Question 41

Metaxylem

Answer 41

Part of primary xylem which differentiates after protoxylem + is distinguished by broader tracheids + vessels with pitted/reticulate walls.

Question 42

Protoxylem

Answer 42

First-formed xylem developing from procambium + consisting of narrow cells with annular, spiral, or scalariform wall thickenings.

Question 43

Collenchyma

Answer 43

Tissue strengthened by thickening of cell walls, as in young shoots.