Bio Lab Practical-Plant Histology

Question 1

Epidermis

Answer 1

Outermost protective layer of cells

Question 2

Root Hair

Answer 2

elongated outgrowth of epidermal cells to increase surface area

Question 3

Cortex

Answer 3

undifferentiated cells between the epidermis and endodermis which allow movement of water and other nutrients

Question 4

Endodermis

Answer 4

single layer of specialized cells which encapsulate the vascular cylinder/stele

Question 5

Casparian Strip

Answer 5

strip embedded in the endodermis composed of suberin, which prevents water and other molecules from moving between the cells of the endodermis
This is significant because it prevents harmful solutes and bacteria from entering the the plant

Question 6

Stele (Vascular Cylinder)

Answer 6

inside the endodermis, composed of several cell types

Question 7

Pericycle

Answer 7

the outermost layer of the stele, responsible for producing lateral roots

Question 8

Lateral Roots

Answer 8

grows through the cortex and eventually erupts out of the epidermis

Question 9

Xylem

Answer 9

vascular tissue that transports water and dissolved mineral nutrients; have thicker walls, larger width, and are dead at maturity,Transport water using water potential, and adhesion/cohesion

Question 10

Phloem

Answer 10

Vascular tissue that transports sugars from sink to source

Question 11

Vascular cambium

Answer 11

zone of actively dividing cells which ultimately differentiate into xylem and phloem

Question 12

Endodermis

Answer 12

Outermost layer of cells

Question 13

Collenchyma

Answer 13

multi-layered region of cells inside the epidermis that contain thickened cell walls which allow the cells to be strong but flexible, aiding in supporting the stem

Question 14

Vascular Bundle

Answer 14

acorn shaped

Question 15

Xylem

Answer 15

The basic function of the xylem is to transport water from roots to stems and leaves, but it also transports nutrients

Question 16

Phloem

Answer 16

the vascular tissue in plants that conducts sugars and other metabolic products downward from the leaves.

Question 17

Vascular Cambium

Answer 17

between the xylem and phloem
Over time, stem will become thicker

Question 18

Fibers (Sclerenchyma tissue)

Answer 18

acorn cap; thick walled elongated cells - cell walls impregnated with lignin, which makes fibers strong for physical support

Question 19

Pith

Answer 19

inside the vascular bundle; composed of undifferentiated, thin-walled parenchyma cells, stores nutrients

Question 20

Epidermis

Answer 20

upper and lower surfaces, single layer of cells
Secretes a waxy cuticle that coats surface of epidermis and prevents water loss

Question 21

Stomata

Answer 21

pores which interrupt the lower epidermis which allow for gas exchange
O2 moves out, CO2 moves into leaf
Surrounded by guard cells: pair of cells around each stoma that can open and close
At bottom of the leaf to prevent excessive water loss

Question 22

Mesophyll

Answer 22

tissue between the upper and lower epidermis where photosynthesis takes place
Palisade mesophyll: layers of tightly packed, elongated cells direction under the upper epidermis
Location due to most exposure to sunlight
Spongy mesophyll: rounder cells surrounded by abundant air spaces

Question 23

Vascular bundles

Answer 23

embedded within the spongy mesophyll, composed of xylem and phloem
Each vascular bundle surrounded by a single layer of cells called the bundle sheath