Cells

Question 1

Plasma membrane

Answer 1

• The boundary of the cell. Regulates the passage of substances into and out of the cell.
• Consists of phospholipids, cholesterol, and protein.
• Phospholipids have a head and rein tails. Head is water loving (hydrophilic) and tails are water fearing (hydrophobic)
• Cholesterol helps stiffin and strengthen the plasma membrane.
• Protein acts as channels allowing solutes to pass in and out. They attach to surface of membrane where they serve as receptors for specific chemicals and hormones. Also have carbohydrates attached to their outer surface which help distinguish between its own cells and foreign cells.

Question 2

Nucleus

Answer 2

The center of the cell and most important part of the cell. Houses DNA/RNA.
Nuclear Envelope-surrounds the nucleus
Nuclear Pores-regulate passage of molecules into the nucleus.
Chromatin-thread like structures composed of DNA and protein.
Chromosomes are rod like structures
-Nucleolus is at the center of the nucleus.
-Ribosomes are the cells protein producing structures

Question 3

Cytoplasm

Answer 3

Gel like substance surrounding the nucleus, packed with various organelles and molecules.

Question 4

Selectively Permeable

Answer 4

Some substances pass through easily while others don’t.

Question 5

Endoplasmic Reticulum

Answer 5

Network of membrane canals and curving sacks.

• Rough ER are studded with ribosomes and synthesize proteins.
• Smooth ER functions as a lipid.

Question 6

Golgi Apparatus

Answer 6

Received proteins from the ER and prepares and packages them for export to other parts of the body.

Question 7

Explain the reason for the variation in cell shape

Answer 7

A cells function dictates its form.
Nerve cell transmits things quickly.
Muscle cells made to contract and expand. Red blood cell have no nucleus, concaved to bend, and hold onto hemoglobin while transporting oxygen.

Question 8

Centrioles

Answer 8

Play a role in cell division

Question 9

Lysosomes “Cellular garbage disposals”

Answer 9

Contain various enzymes that help break down the protein the cell doesn’t need.
Allows cell to reuse amino acids and destroy bacteria

Question 10

Microvilli

Answer 10

Greatly increase surface area of cell, usually found in intestines.
Don’t move

Question 11

Facilitated Diffussion

Answer 11

Needs other molecules to help their movement across the membrane.
Moves down the concentration gradient from greater to leaser concentration.

Question 13

Flagella “headache”

Answer 13

Sperm

Question 14

Diffusion

Answer 14

The movement of particles from an area of higher concentration to an area of lower concentration.

Question 15

Osmosis

Answer 15

Involves the diffusion of water down the concentration gradient through a selectively permeable membrane.

Question 16

Filtration

Answer 16

Occurs because of differences in pressure.

Water and dissolved particles are forced across a membrane of higher to lower hydrostatic pressure.

Question 17

Active transport

Answer 17

Requires energy and includes transport by pumps and vesicles.

Question 18

Transport by vesicles

Answer 18

Process which requires energy where the cell membrane creates a vesicle to transport the matter into a cell or out of the cell.

Endocytosis bring substances into the cell; phagocytosis-cell eating and pinocytosis-cell drinking.
Exocytosis-is vesicles to release substances outside the cell.

Question 19

Osmolality

Answer 19

Involves the diffusion of water down the concentration gradient through a selectively permeable membrane.

Question 20

Tonicity

Answer 20

Ability of a solution to affect the fluid volume and pressure in a cell through osmosis.

Question 21

Isotonic

Answer 21

Which the concentration of solute is the same as it is in the cell.

Question 22

Hypertonic

Answer 22

Solutions contain a higher concentration of solute compared to the fluid within the cell.

Question 23

Hypotonic

Answer 23

Solution contains a lower concentration of solute compared to the fluid within the cell.

Question 24

1. Prophase
2. Metaphase
3. Anaphase
4. Telophase

Answer 24

1. Chromatin begins to coil and condensed to form chromosomes.
2. Some of the spindle fibers attached to one side of the chromosomes at the centromere and the chromosomes line up along the center of the cell.
3. Centromere’s divide forming two chromosomes instead of a pair of attached chromatids.
4. A new nuclear envelope develops around each set of daughter chromosomes and produces two identical daughter cells.

Question 25

Mitosis

Answer 25

When the cell splits into two identical daughter cells.

Question 26

Cytoskeleton

Answer 26

Framework of the cell. Determines cell shape. Strengthens cell. Allows cells to move.

Question 27

Passive transport

Answer 27

Requires no energy and includes diffusion, osmosis, filtration, and facilitated diffusion.

Question 28

Cells

Answer 28

Carry out all chemical activities needed to sustain life. Building blocks of all living things.

Question 29

Organelles

Answer 29

“Little organs”

Inside cytoplasm and form specific tasks.

Question 30

Ribosomes

Answer 30

Made of protein and rna

Sites of protein synthesis

Question 31

Solution

Answer 31

A mixture of 2 or more components.
Solvent – dissolving medium, water in the body.
Solutes -components in smaller quantities with a solution.

Question 32

Stem cells

Answer 32

Special cells that divide. Embryonic cells occur in the early embryo, can differentiate into 200 or more. Adult stem cells – occur in certain organs

Question 33

Cilia

Answer 33

Hair like
Move
1direction
Helps move mucus and foreign particles out