U1T7 - Keywords Flashcards Preview

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Flashcards in U1T7 - Keywords Deck (43)
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1
Q

Alimentary Canal

A

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.

2
Q

Chyme

A

Mix of food and gastric juice.

3
Q

Duodenum

A

First loop of the small intestine

4
Q

Pyloric Sphincter

A

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

5
Q

Muscularis Mucosa

A

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.

6
Q

Serosa

A

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.

7
Q

Mesentery

A

Fold of the peritoneum which attaches

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

8
Q

Peritoneum

A

Serous membrane lining cavity of abdomen + covering abdominal organs.

9
Q

Serous

A

Serum-producing.

10
Q

Goblet Cells

A

Mucus secreting cells within columnar epithelial cells.

11
Q

Bile

A

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

12
Q

Bile Salts

A

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

13
Q

Crypts of Lieberkuhn

A

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

14
Q

Brunner’s Glands

A

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

15
Q

Epidermis

A

Covers + protects leaf. First defence against physical damage.

16
Q

Upper Epidermis

A

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.

17
Q

Lower Epidermis

A

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.

18
Q

Vascular Tissue

A

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

19
Q

Vascular Bundles

A

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

20
Q

Xylem

A

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

21
Q

Phloem Sleeve/Sieve-Tubes

A

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.

22
Q

Palisade Mesophyll

A

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

23
Q

Spongy Mesophyll

A

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.

24
Q

Tissues

A

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

25
Q

Organs

A

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

26
Q

Organ Systems

A

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

27
Q

Pinocytosis

A

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

28
Q

Venules

A

Small Vein

29
Q

Villi

A

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

30
Q

Microvilli

A

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

31
Q

Specialised Cells

A

Adapted to carry out a particular function.

32
Q

Cell

A

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

33
Q

Peristalsis

A

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

34
Q

Segmentation

A

Division of a cell, cleavage.

35
Q

Pendular Movement

A

Swinging movement of intestine without peristaltic action, mixing food.

36
Q

Smooth Muscle

A

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

37
Q

Arteriole

A

Small branch of artery leading into capillaries.

38
Q

Petiole

A

The stalk that joins a leaf to a stem.

39
Q

Midrib

A

Large strengthened vein along midline of leaf.

40
Q

Waxy cuticle

A

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

41
Q

Metaxylem

A

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

42
Q

Protoxylem

A

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

43
Q

Collenchyma

A

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